Question

Solve the system x + y = 6 and x - y = 2. What is the value of x?
A. 6
B. 2
C. 4
D. 0

Answer 1

x+y=6
x-y=2


Add the equations to get


(x+y)+(x-y)=6+2

(x+x)+(y-y) = 8

2x = 8

x = 8/2

x = 4

Answer 2

The best way to tackle this problem would be to simply add both equations to obtain 2x=8, x=4. Finally, you plug this solution into any of the two equations above to obtain 4+y=6, y=2.

Answer 3

thank you @jim_thompson5910

Answer 4

np, glad to be of help

Answer 5

Which of the following is a solution for the system y = -3x + 5 and y = 2x + 5?
A. (1, 7)
B. (5, 0)
C. (2, -1)
D. (0, 5)

Answer 6

y = -3x + 5

2x+5 = -3x + 5

2x+3x = 5-5

5x = 0

x = 0/5

x =0

-------------

y = -3x+5

y = -3(0)+5

y = 0+5

y = 5

So the answers are x = 0 and y = 5 giving the answer to be choice D) (0, 5)

Answer 7

Thank youu!! I have other questions too. I'm sorry to be a bother to you but you're the only one who is really helping me out. You don't just give the answer, you show how to get that answer. And I'm in a rush to get this stuff done because it has to be done by tomorrow. Could you help me with the rest of the questions I have?

Answer 8

sure, would love to

Answer 9

don't mind helping out as long as you're learning and taking notes (that's why i do all the steps)

Answer 10

thanks soo much!! (:
Okay.. next question is:

Simplify: (2x + 8)(2x - 8).
A. 4x^2 - 16
B. 4x^2 - 64
C. 4^x2 - 16x - 64
D. 4x^2 - 8x + 16

Answer 11

I am taking notes, definitely!!

Answer 12

(2x + 8)(2x - 8)


(2x)(2x) + (2x)(-8) + (8)(2x) + (8)(-8) ... *** Note: use the FOIL rule here


4x^2 - 16x + 16x - 64


4x^2 - 64


So the answer is choice B


***Side note: this is a difference of squares ***

Answer 13

that's good, hope it's all making (some) sense