It's a simultaneous equation:
Steps:
1.Number the equations..
a+b=77 -1
a-b=13 -2
2. Choose what variable you want to use. In this case I would use the "b". Since the signs in front of the "b's" are different, add the two equations together
a + b = 77
+ + +
a (-b) = 13
Which gives;
2a = 90
Then solve to find a:
2a=90
a= 90/2
a=45
3.Then plug the "a" value into any of the original equations to find the "b" value. I would use equation 1 since the all the variables are positive.
a + b = 77
(45) + b = 77
b=77-45
b=32
4.Solution
a=45
b=32
Answer:

Step-by-step explanation:
Given expression:

Remove parentheses:

Collect like terms:

Combine like terms:

Slope = -1/4
(4, 7)
y - 7 = -1/4 (x - 4)
y - 7 = -1/4x + 1
y = -1/4 + 8
answer is C
Answer:
x=-2
Step-by-step explanation:
4+8x=-12
-4 -4
8x = -16
/8 /8
x = -2
Answer:
<em>All real solutions.</em>
Step-by-step explanation:
5(- 3x - 2) - (x - 3) = -4(4x + 5) + 13
-15x-10-x+3=-16x-20+13
-16x-7=-16x-7
All real solutions.
hope this halps... :D lol