# Question #4c8a8

##### 1 Answer

Mar 18, 2017

#### Explanation:

We have the following equations.

#xcolor(red)(+y)=10to(1)#

#color(red)(y)=4xto(2)# Solve using the

#color(blue)"substitution method"# That is substitute

#color(red)(y)=4x" into " (1)#

#rArrx+4x=10#

#rArr5x=10# divide both sides of the equation by 5

#(cancel(5) x)/cancel(5)=10/5#

#rArrx=2# Substitute this value into ( 2 ) to obtain value for y

#rArry=4xx2=8#

#color(blue)"As a check"# Substitute these values into the original statements and if they are true then these are the solutions.

#x+y=2+8=10to" True"#

#y=4xx2=8to" True"#

#rArrx=2" and "y=8" are the solution"#