Question

could someone help me solve this equations with both comparison and elimination methods: 2(x+y)=120 and 2(2x+y/3)=170​

Answer 1

y=21 X=39

Explanation:

expand brackets on first equation: 2x+2y=120

now divide the second equation by 2 on both sides:

2x+y/3=85

then subtract the second equation from the first equation

so (2x+2y) - (2x+y/3)

the 2x on both sides cancel out and you get 5/3 y

this is equal to the sum of the first equation subtract the second equation which is 35

divide both sides by 5/3 and you get

y=21

substitute y in the first equation and you get X=39