Answer:
Explanation:
3x+4y = 17 _______ equation 1
-4x -7y= -18 _______ equation 2
muliply by 4 in equation 1
12x + 16y = 68 ______ equation 3
multiply by 3 in equation 2
-12x - 21y = -54 ________ equation 4
add equation 3 & 4
- 5y = 14
y = - 14/5
substitute y in equation 1
3x + 4 (-14/5) =17
3x = 17+ (56/5)
3x =( 85 + 56) / 5
3x = 141/5
x = 47/5
hence (a,b) = (47/5, -14/5)