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.

Answer 1

I will give medals Please help me

Answer 2

Set the equation equal to each other

Answer 3

how can i do that im not really good at that

Answer 4

Since both of them are equal to y you set the equation to be 8x-9=4x-1

Answer 5

okay and then what?

Answer 6

Combine Like terms. Bring 4x to the other side by subtracting and combine like terms

Answer 7

so minus the 4 and what other number?

Answer 8

So 8x-4x=4x-9=-1

Answer 9

Since 8x and 4x share a x they are like terms and you can combine them

Answer 10

So now solve 4x-9=-1

Answer 11

so now we have 4x - 9 = -1

Answer 12

yes. Bring nine to the other side by adding and divide by 4

Answer 13

does the 1 has to be negative?

Answer 14

yes since it is negative from the original equation

Answer 15

or you can add one to the other side to make it positive but thats an extra step

Answer 16

Okay so 4x - 9 = -1
/4 /4 Right?

Answer 17

no first you add 9. 9+-1=8

Answer 18

What did u add?\

Answer 19

So you understand how we got 4x-9=-1 Right?

Answer 20

yes but what is next

Answer 21

So to solve for x bring 9 to the other side. Since 9 is negative on the other side you do the opposite and add

Answer 22

4x=9+-1

Answer 23

9+-1 is 8. Divide by 4 and get 2

Answer 24

So the solution is 2

Answer 25

x=2

Answer 26

okay can u help me with one more?

Answer 27

sure

Answer 28

A pair of equations is shown below:

y = 7x – 9
y = 3x – 1

Part A: In your own words, explain how you can solve the pair of equations graphically. Write the slope and y-intercept for each equation that you will plot on the graph to solve the equations.

Answer 29

Ok same thing here set each equation equal to each other

Answer 30

so 7x-9 = 3x - 1?

Answer 31

Yes. Now combine like terms

Answer 32

do I add the 7 or 3