Question 1005595


Renee's dad hired her for {{{11}}} hours and paid ${{{368}}}.

let the number hours of English be {{{x}}} and  the number hours of  Math be {{{y}}}

if Renee's dad hired tutor for {{{11}}} hours, then

{{{x+y=11}}}.......eq.1 
if an hour of English cost ${{{22}}} and an hour of Math is ${{{40}}}, and Renee paid ${{{368}}}, we have

{{{22x+40y=368}}}..........eq.2

solve the system:

{{{x+y=11}}}.......eq.1 .............both sides multiply by {{{22}}}
{{{22x+40y=368}}}..........eq.2
-----------------------------------
{{{22x+22y=242}}}.......eq.1
{{{22x+40y=368}}}..........eq.2
-----------------------------------..............subtract eq.1 from eq.2

{{{22x+40y-22x-22y=368-242}}}

{{{18y=126}}}

{{{y=126/18}}}

{{{highlight(y=7)}}}

now find {{{x}}}


{{{x+y=11}}}.......eq.1

{{{x+7=11}}}

{{{x=11-7}}}

{{{highlight(x=4)}}}

Renee's dad  paid ${{{4*22=88}}} for English and  ${{{7*40=280}}} for Math which make total of ${{{88+280=368}}}