# Solving and replacing solution for solving again

Given some equation to solve

S1=Solve[f[x,z]==g[x,z],x]//Simplify


which produces something like

x->xsol[z]


I write another equation that must use the result above, so

S2=Solve[h[x,y,z]==j[x,y,z],y]/.S1//Simplify


but it gives

y-> y[(x->xsol),z]


I mean, it didnt replace x=xsol. How can I improve this steps?

• Move the /.S1 inside the Solve and attach it to the equation instead? – march Sep 23 '15 at 20:57

Use the replacement, i.e. /.S1 inside the solver. That is,
S2=Solve[h[x,y,z]==j[x,y,z]/.S1,y]//Simplify
{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8459067344665527, "perplexity": 6243.551495960539}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-47/segments/1573496668699.77/warc/CC-MAIN-20191115171915-20191115195915-00320.warc.gz"}