two poles of height 6 m and 11 m, respectively stand on a plane ground. if the distance between thei&#8230;.
two poles of height 6 m and 11 m, respectively stand on a plane ground. if the distance between their feet is 12 m, then what is the distance between their tops?
two poles of height 6 m and 11 m, respectively stand on a plane ground. if the distance between their feet is 12 m, then what is the distance between their tops?
eliminte ?, 1) if x=3 sec ? + 4 tan ? and y=4 sec ?- 3 tan ?. 2) the angles of dipression of the top and bottom of 8 meter tall building from the top of multistoried building are 30â° and 45â° respectively.find the height of multistoried building and the distance between two buildings (?3=1.73) answer: 15
solution: there are six straight lines `l\_(1),l\_(2),l\_(3),l\_(4),l\_(5),l\_(6)` in a plane.   
 since no two lines are parallel and no three of which pass through the same point, we have maximum points of intersection.   
 line `l\_(1)` intersect five lines, so there will be five points of intersection.   
 similarly, for each of the lines `l\_(2),l\_(3),l\_(4),l\_(5),l\_(6)`, there will be five points of intersection.   
 but there will be double counting .   
 so, total number of points of intersection is `(5xx6)/(2)=15` the straight distance between two place on a map can be measured by a strip of paper and divider.use a ruler to measure the distance between the two places. if the line is quite curved, use a string to determine the distance, and then measure the string. find the scale for the map you're going to use. it might be a ruler bar scale or a written scale, in words or numbers. floor lamps should have an overall height of roughly 58”-64” (147-163 cm) based on the standard sitting height of a person on a couch or chair. the bottom of the floor lamp shade should be roughly at or above a person’s sitting eye level and should try to match the edges of similar lighting fixtures within the space. 185 cm / 6.1 ft 189 cm / 6.2 ft the north pole sits on a floating ice sheet which is called the arctic ice sheet. there is no land underneath it, but the sea depth at the north pole has been measured at 4,261 metres (13,980 ft). because of this, the north pole is incapable of supporting any plant or animal life on it. hello again curtin,you will need to visit the water parks site and click on each attraction (for each of the water parks)that you are interested in. each one will list their height requirements or other special restrictions. an example of this is the downhill double dipper (cool dude!), which is located at blizzard beach and has a height requirement of 48 (122cm) or taller (listed underneath the description of the attraction). one of my favorites at typhoon lagoon is humunga kowabunga with a height restriction of 48 (122cm) or taller as well. enjoy your time at the water park's and remember to use that sunscreen...it can get real hot there. have a magical day!brigitta hint: assume the co-ordinates of $r$ as $(x,y)$ and as it is given that $p,q,r$ are collinear points. apply distance condition of collinear points which is if $p,q,r$ are three collinear points then they must satisfy $pq+qr=pr$ and get one equation. apply distance formula which states that if $a({{x}\_{1}},{{y}\_{1}})$ and $b({{x}\_{2}},{{y}\_{2}})$ are two points then the distance $ab=\sqrt{{{({{x}\_{2}}-{{x}\_{1}})}^{2}}+{{({{y}\_{2}}-{{y}\_{1}})}^{2}}}$ and get the second equation by using $pr=10$ , solve these two equations and get the co-ordinates of $r$. complete step-by-step solution:it is given in the question that $p, q, r$ are collinear points.collinear means lying on the same line which means that $p, q, r$ lies on the same straight line.let us suppose that the co-ordinates of $r$ is $(x,y)$. now, we have $p(7,7)$, $q(3,4)$, $r(x,y)$ and also $pr=10$.we have to use distance formula in order to find $pq,qr,pr$. so, according to distance formula if $a({{x}\_{1}},{{y}\_{1}})$ and $b({{x}\_{2}},{{y}\_{2}})$ then $ab=\sqrt{{{({{x}\_{2}}-{{x}\_{1}})}^{2}}+{{({{y}\_{2}}-{{y}\_{1}})}^{2}}}$.now, $p,q,r$ are three collinear points then they must satisfy,$\therefore pq+qr=pr$using distance formula, we get$\rightarrow \sqrt{{{(7-3)}^{2}}+{{(7-4)}^{2}}}+\sqrt{{{(3-x)}^{2}}+{{(4-y)}^{2}}}=10$$\rightarrow \sqrt{16+9}+\sqrt{{{(3-x)}^{2}}+{{(4-y)}^{2}}}=10$$\rightarrow 5+\sqrt{{{(3-x)}^{2}}+{{(4-y)}^{2}}}=10$\[\rightarrow \sqrt{{{(3-x)}^{2}}+{{(4-y)}^{2}}}=5\]squaring both sides, we get$\rightarrow {{(3-x)}^{2}}+{{(4-y)}^{2}}=25$$\rightarrow {{x}^{2}}+{{y}^{2}}-6x-8y+25=25$cancelling 25 from both sides, we get$\rightarrow {{x}^{2}}+{{y}^{2}}=6x+8y...................(1)$also, it is given that $pr=10$, using this we get$\therefore pr=10$\[\rightarrow \sqrt{{{(7-x)}^{2}}+{{(7-y)}^{2}}}=10\]squaring both sides, we get\[\rightarrow {{(7-x)}^{2}}+{{(7-y)}^{2}}=100\]$\rightarrow {{x}^{2}}+{{y}^{2}}-14x-14y+98=100$putting the value of ${{x}^{2}}+{{y}^{2}}$ from equation (1), we get$\rightarrow 6x+8y-14x-14y=100-98$$\rightarrow -8x-6y=2$now, expressing $y$ in terms of $x$, we get$\rightarrow y=\dfrac{-(2+8x)}{6}=\dfrac{-(1+4x)}{3}..................(2)$putting the value of $y$ from equation (2) in equation (1), we get$\rightarrow {{x}^{2}}+{{\left( \dfrac{-(1+4x)}{3} \right)}^{2}}=6x+\dfrac{-(1+4x)}{3}\times 8$$\rightarrow \dfrac{9{{x}^{2}}+1+8x+16{{x}^{2}}}{9}=\dfrac{18x-8-32x}{3}$$\rightarrow 25{{x}^{2}}+8x+1=3(-14x-8)$$\rightarrow 25{{x}^{2}}+8x+1+42x+24=0$$\rightarrow 25{{x}^{2}}+50x+25=0$$\rightarrow 25({{x}^{2}}+2x+1)=0$$\rightarrow {{(x+1)}^{2}}=0$$\rightarrow x+1=0\rightarrow x=-1$now, putting the value of $x$ in equation (2), we get$\rightarrow y=\dfrac{-(1+4\times -1)}{3}$$\rightarrow y=\dfrac{3}{3}=1$so, $x=-1$ and $y=1$.hence the co-ordinates of $r$ is $(-1,1)$. note: this question is simple and there are many other alternative ways to solve it but the tricky part is to choose which method to solve the question. there are three different conditions of collinearity as there is slope condition, distance condition, and area condition. as in the other two conditions distances are not involved, only the distance condition involves the use of distances. in the question, distance is mentioned so we choose that method to solve it. hence, students should carefully read the question and choose which method is suitable to solve the question according to the values given. since the image is formed on the screen, the image is real. a concave lens cannot form a real image. therefore, the lens is convex.object distance, u = -30 cmimage distance, v = +60 cmaccording to lens formula:f = +20 cmmagnification of convex lens, m = thus the image of the candle flame is 6 cm high and inverted (as indicated by the –ve sign)