Question

Find the values of a and b so that the solution of the linear system is (-9,1).

ax + by = -31
ax – by = -41

Answer 1

Explanation:

we can write -9 instead of x and y=1 instead of 1

so we write solution again

-9a+1b=-31

-9a-1b=-41

-18a=-72

a=4

we should write 4 instead of a

-9(4)+1b=-31

-36+b=-31

b=5

a=4