Question

Solve the following system of equations. Express your answer as an ordered pair in the format (a,

b., with no spaces between the numbers or symbols.2x+5y=16 -5-2y=2

Answer 1

The second equation is -5-2y=2, then

-2y=2-(-5),

-2y=2+5,
-2y=7,
y=7÷(-2),
y=-3.5.
The first equation is 2x+5y=16, subtitude y=-3.5 in this equation, then
2x+5·(-3.5)=16,
2x-17.5=16,
2x=16-(-17.5),
2x=16+17.5,
2x=33.5,
x=33.5÷2,
x=16.75.
Answer: (16.75,-3.5)

Answer 2

(x,y) = (-2,4)

Explanation:

Consider the system of equation,

2x + 5y = 16 .......... (1)

-5x - 2y = 2 ......... (2)

Using Elimination method to solve the system of equation,

Multiply equation (1) by 5 , we get,

10x + 25y = 80 ...........(3)

Multiply equation (2) by 2 , we get,

-10x - 4y = 4 ......... (4)

Adding (3) and (4) , we get,

10x + 25y +( -10x - 4y )= 4 + 80

10x and -10x got cancel, we get,

25y - 4y = 84

⇒ 21y = 84

⇒ y = 4

Put y = 4 in (1),

2x + 5(4) = 16 ⇒ 2x = 16 - 20 ⇒ 2x = -4 ⇒ x = -2

Thus, (x,y) = (-2,4)