Answer:
C
Explanation:
We can solve simultaneous equations using substitution method, elimination method or graphical method. But for this purpose, we will be using the elimination method.
3x+4y=8 Equation 1
2x+y=42 Equation 2
Multiply Equation 1 by 2 and equation 2 by 3, so as to get the same coefficient for x
2(3x+4y=8)= 6x+8y=16 Equation 3
3(2x+y=42)= 6x+3y=126 Equation 4
Subtract equation 4 from 3, to eliminate x
6x-6x=0
8y-3y= 5y
16-126= -110
We now have 5y=-110
Divide both sides by 5,
y= -110/5
= -22
Substituting for y in equation 2
2x+(-22)= 42
2x= 42+22
2x=64
x= 64/2
= 32
(x, y)
(32, -22)