Answer:
x = 6
y = -3
Explanation:
15x + 31y = -3
we are given that x =( - y + 3 )
so in the equation 15x + 31y = -3 we substitute "x" for ( -y + 3 ) and we solve for y
so 15 ( -y + 3 ) + 31y = -3
now we use basic algebra to solve for y
step 1 distribute the 15
15 * -y = -15y
15 * 3 = 45
now we have 45 - 15y + 31y = -3
step 2 combine like terms
-15 + 31y = 16y
now we have 45 + 16y = -3
step 3 subtract 45 from each side
-3 - 45 = -48
45 - 45 cancels out
now we have 16y = -48
step 4 divide each side by 16
16y/16=y
-48/16=-3
we're left with y = -3
Now to find x we substitute -3 for y in x = -y + 3
* substitute *
x = - ( -3) + 3
the two negative signs cancel out and we get x = 3 + 3
3 + 3 = 6
we're left with x = 6