Question

I have five questions i need answered. Its solving systems! Can some one help?

Answer 1

whats the problem ?

Answer 2

i have to do number 82-86 and i cant figure any of them out i did 81 but they were really hard

Answer 3

http://www.slideshare.net/leblance/chapter-4-extra-practice-answers

Answer 4

please please please help

Answer 5

pleeeeeeease help im begging

Answer 6

I am not too good at these....

y = x^2 + 2x - 8 ....(y = x + 4)
now we sub
x + 4 = x^2 + 2x - 8
x^2 + 2x - x - 8 - 4 = 0
x^2 + x - 12 = 0
(x - 3)(x + 4) = 0

x - 3 = 0
x = 3

x + 4 = 0
x = -4

x = 3 and x = -4

now I am guessing you just sub both of those answers into y = x + 4, and solve for y ??

Answer 7

see if it works

Answer 8

i got that one right! :D yay!

Answer 9

when x = 3, y = x + 4
y = 3 + 4
y = 7
and
when x = -4, y = x + 4
y = -4 + 4
y = 0

check..
y = x^2 + 2x - 8
7 = 3^2 + 2(3) - 8
7 = 9 + 6 - 8
7 = 15 - 8
7 = 7 (correct)

y = x^2 + 2x - 8
0 = -4^2 + 2(-4) - 8
0 = 16 - 8 - 8
0 = 0 (correct)

Answer 10

can you help me especiially with number 84-86 cause i dont understand those at alllll

Answer 11

y = x^2 - 3x - 7
y = -x^2 - x + 5
set them equal to each other

x^2 - 3x - 7 = -x^2 - x + 5
x^2 + x^2 - 3x + x - 7 - 5 = 0
2x^2 - 2x - 12 = 0
2(x + 2)(x - 3)

x + 2 = 0
x = -2

x - 3 = 0
x = 3

now pick an equation and sub in your x answers for y
y = x^2 - 3x - 7
y = -2^2 - 3(-2) - 7
y = 4 + 6 - 7
y = 10 - 7
y = 3

y = x^2 - 3x - 7
y = 3^2 - 3(3) - 7
y = 9 - 9 - 7
y = -7

Answer 12

can you do 86? im so confused!!! ive never seen fraction in them. my teacher didnt go over it

Answer 13

y = x^2 - 2x - 1
y = 3/4x^2 + x - 6
set them equal

x^2 - 2x - 1 = 3/4x^2 + x - 6
4/4x^2 - 3/4x^2 - 2x - x - 1 + 6 = 0
1/4x^2 - 3x + 5 = 0

Oh crap....I am sorry. I do not know what to do next :( I am probably totally wrong on this...sorry again

Answer 14

its ok

Answer 15

85?

Answer 16

i figured them out...for future reference..you divide 1/4 by all 3 numbers to get answers!