5.Regarding the equations below. What is the value of x? 5x + 2y = 4 x – 3y = –23

Mathematics

1 answer:

insens350 [35]3 years ago

3 0

Answer:

x=−2

y=7

Step-by-step explanation:

5x+2y=4

x−3y=−23

In order to solve by elimination, coefficients of one of the variables must be the same in both equations so that the variable will cancel out when one equation is subtracted from the other.

5x+2y=4,x−3y=−23

To make 5x and x equal, multiply all terms on each side of the first equation by 1 and all terms on each side of the second by 5.

5x+2y=4,5x+5(−3)y=5(−23)

Simplify.

5x+2y=4,5x−15y=−115

Subtract 5x−15y=−115 from 5x+2y=4 by subtracting like terms on each side of the equal sign.

5x−5x+2y+15y=4+115

Add 5x to −5x. Terms 5x and −5x cancel out, leaving an equation with only one variable that can be solved.

2y+15y=4+115

Add 2y to 15y.

17y=4+115

Add 4 to 115.

17y=119

Divide both sides by 17.

y=7

Substitute 7 for y in x−3y=−23. Because the resulting equation contains only one variable, you can solve for x directly.

x−3×7=−23

Multiply −3 times 7.

x−21=−23

Add 21 to both sides of the equation.

x=−2

The system is now solved.

x=−2,y=7

Graph if needed:

You might be interested in

An irregular parallelogram rotates 360° about the midpoint of its diagonal. How many times does the image of the parallelogram c

Ad libitum [116K]

Answer:

The correct options is A.

Step-by-step explanation:

The each diagonal of an irregular parallelogram divides the parallelogram in two equal and congruent parts. The diagonal bisects each other.

It means, if a irregular parallelogram rotates 180° about the midpoint of its diagonal, then the image of the parallelogram coincide with its preimage during the rotation.

If a irregular parallelogram rotates 360° about the midpoint of its diagonal, then the image of the parallelogram coincide 2 times with its preimage during the rotation.

Therefore the correct option is A.