Question

Solve the equation for y.

4x – 5y = 9

A.  y = 4/5x - 9/5

B.  y = 5/4x + 9/4

C.  y = -5/4x - 5/9

D. -4x - 9

Which ordered pairs in the form (x, y) are solutions to the equation 4x – 5y = 24?

 Choose all answers that are correct.                                 

A. (−9, −12)                                               

B. (1, −4)                                                        

C. (4, 8)                                                        

D. (6, 0)

Answer 1

1. 4x – 5y = 9
⇒4x = 5y +9
⇒4x -9 = 5y
⇒(4x -9)/5 = 5y/5
⇒y = (4x-9)/5
⇒y = (4/5)x - 9/5

2. To check whether they are solution or not, put the values in the equation and see if it satisfies the equation or not.
Equation is 4x – 5y = 24 or 4x – 5y - 24 = 0

A. 4(-9) – 5(-12) - 24 = -36 +60 -24 = 0   <<<<<<<<solution
B. 4(1) – 5(-4) - 24 = 4+20-24 = 0   <<<<<<<<<<<<solution
C. 4(4) – 5(8) - 24 = 16 -40-24 =-48  <<<<<<<<<<<not a soluton
D. 4(6) – 5(0) - 24 = 24 -0-24 = 0<<<<<<<<<<<<<< solution.

Answer 2

1.
4x-5y=9

⇒-5y =9-4x

applying - on both sides

⇒-(-5y)=-(9-4x)

⇒5y= -9+4x

⇒y=4x-9÷5

⇒y=4x/5-9/5(A)

2.4x -5y=24

A.4(-9)-5(-12)=24⇒-36-(-60)⇒-36+60⇒24 A-SATISFIED

B.4(1)-5(-4)⇒4-(-20)⇒4+24⇒24 B-SATISFIED

C.4(4)-5(8)⇒24-40⇒-14 C-NOT SATISFIED

D.4(6)-5(0)⇒24-0⇒24 D.SATISFIED

SO A,B AND D ARE SOLUTIONS FOR THIS EQUATION.