Question

A pair of equations is shown below:

y = 8x - 9
y = 4x - 1

Part A: Explain how you will solve the pair of equations by substitution or elimination. Show all the steps and write the solution.

Part B: If they 2 equations are graphed, at what point will the lines representing the two equations intersect? Explain your answer.

Answer 1

A: (2, 7)

B: (2, 7)

Explanation:

Part A: (substitution)

y = 8x − 9

y = 4x − 1

Both are equal.

8x − 9 = 4x − 1

Then, subtract 4x from both sides.

4x − 9 = -1

Add 9 to both sides.

4x = 8

Finally, divide by 4.

x = 2

Substitute for x.

y = 4(2) - 1

y = 8 - 1

y = 7

Solution: (2, 7)

Part B:

At (2, 7)