Presumably this is a simultaneous equation question. 5x-7y = -40 3x = 2y-24 3(5x-7y = -40) 5(3x-2y = -24) After aligning the letters and numbers multiply the top equation by 3 and the bottom equation by 5. Note that 2y is now -2y because it has moved over to the other side of the equation. 15x-21y = -120 15x-10y = -120 To eliminate x subtract the bottom equation from the top equation remembering that a - - is equal to a + 0-11y = 0. So y will = 0 Substitute the value of y into the equations to find the value of x Solution: x = -8 and y = 0
y=16 x= -4
7x-40 = -3x Add 40 and add 3x to both sides:- 7x-40+40+3x = 3x-3x+40 10x = 40 Divide both sides by 10:- x = 4
8 - 3x = 128subtract 8 from each side-3x = 120divide each side by -3x = -40
-3x + 40 = 38 Subtract 40 from both sides: -3x = -2 Multiply both sides by -1: 3x = 2 Divide both sides by 3: x = 2/3
2x+9 = 49-3x 2x+3x = 49-9 5x = 40 x = 8
y=16 x= -4
4y = 2y + 40 4y - 2y = 2y -2y +40 2y = 40 y = 20 check 4(20) = 2(20) +40 80 = 80
3x + 2x = 40 5x = 40 x = 8
4x + 10 + 3x = 40 - 3x 4x + 10 + 3x + 3x = 40 20x = 40 x = 2
x + 3x = 40 4x = 40 x = 10.
7x-40 = -3x Add 40 and add 3x to both sides:- 7x-40+40+3x = 3x-3x+40 10x = 40 Divide both sides by 10:- x = 4
6y-2y=40 6-2=40/y 4=40/y y=10 6(10)-2(10)=40
10 - 3x = x - 2x + 40 10 - 3x = - x + 40 10 - 40 = 3x - x -30 = 2x -15 = x
2y-5=11y+40 Subtract 2y from both sides -5=9y+40 Subtract 40 from both sides. -45=9y Divide by 9. -5=y
8-3x = 128 -3x = 128-8 -3x = 120 x = -40
8 - 3x = 128subtract 8 from each side-3x = 120divide each side by -3x = -40
-3x + 40 = 38 Subtract 40 from both sides: -3x = -2 Multiply both sides by -1: 3x = 2 Divide both sides by 3: x = 2/3