Question

If x+y=4a+7 and x-y=2a+5, solve for x in terms of a

A. 2a+2
B. 2a+5
C. 2a+6
D. 3a+4
E. 3a+6

Answer 1

A

Explanation:

x + y = 4a + 7

x - y = 2a + 5

In both equations, make x the subject of the formula

x = 4a + 7 - y equation 1

x = 2a + 5 + y equation 2

Subtract equation 2 from equation 1

2a + 2 -2y

= 2a + 2