3x-2y=9 and y=2x-7 solve each system of linear equations by substitution. step by step .

Y = 2x - 7so sub in 2x - 7 for y in the other equation

3x - 2y = 9
3x - 2(2x - 7) = 9distribute thru the parenthesis
3x - 4x + 14 = 9subtract 14 from both sides
3x - 4x = 9 - 14...simplify
-x = - 5...multiply by -1 to make x positive
x = 5

now sub 5 in for x in either of ur original equations to find y

y = 2x - 7
y = 2(5) - 7
y = 10 - 7
y = 3

now we can check our answers...(5,3)

3x - 2y = 9
3(5) - 2(3) = 9
15 - 6 = 9
9 = 9 (correct)

so ur solution is : (5,3) <==