Question

Solve the following systems of equations using the substitution method. What is the value of a? 3a-5b=10 a+7b=12 A) a=5 B) a=6 C) a=1 D) a=7

Answer 1

i hope its clear . the answer is a = 5

Answer 2

a=5

Explanation:

3a-5b=10

a+7b=12

multiply the second row with -3

-3a-21b=-36 now we gonna add this to the first row

3a-5b=10

_________+

-26b=-26 b=1 now we gonna put in one of the equations to find a

a+7b=12

a+7.1=12 a=5