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Can someone please have a heart to help me this is for a grade

Can someone please have a heart to help me this is for a grade-example-1
User Supi
by
5.8k points

2 Answers

1 vote

Answer:

(-4, 5)

Explanation:

Since y = -3x - 7 in the first equation, substitute y of the second equation with -3x - 7:

-3x - 7 = x + 9

Subtract x from both sides. Add 7 to both sides.

-4x = 16

Divide both sides by -4.

x = -4

Now, substitute -4 for x in the second equation.

y = -4 + 9

y = 5

The solution is:

x = -4; y = 5

As an ordered pair, the solution is:

(-4, 5)

User Vadym Chumel
by
5.7k points
4 votes

Hey there!

Let's start by solving for x.

Take the first equation, y = -3x - 7, and substitute in the second equation, y = x + 9, for y.

We now have:

x + 9 = -3x - 7

Add 3x to both sides.

4x + 9 = -7

Subtract 9 from both sides.

4x = -16

Divide each side by 4.

x = -4

Let's use the second equation, y = x + 9, to solve for x.

Put in the value we just solved for.

We now have:

y = -4 + 9

Simplify.

y = 5

Let's check our answer, starting with the first equation, y = -3x - 7.

Put in the values for x and y.

5 = -3(-4) - 7

5 = 12 - 7

5 = 5

Do the same with the second equation, y = x + 9.

5 = -4 + 9

5 = 5

The solution to the system of equations is (5, -4).

Hope this helps!

User Chris Lacasse
by
5.8k points