Answer:
x = 5
Step-by-step explanation:
Given
13 = - 7 + 9x - 5x , that is
13 = - 7 + 4x ( add 7 to both sides )
20 = 4x ( divide both sides by 4 )
5 = x
Answer:
Im confused what your trying to get at is there a picture or something
Step-by-step explanation:
Answer:
f(-3) = 9
Step-by-step explanation:
Step 1: Define
f(-3) = x = -3
f(x) = x²
Step 2: Substitute and Evaluate
f(-3) = (-3)²
f(-3) = 9
Answer:
The third side is around 58.043
Step-by-step explanation:
Use the law of cosines: 
Plug in the two sides we know (into a and b) and the angle we know (into angle C).
Thus:
Use a calculator:
(Note: Make sure you're in Degrees mode.)
Answer:
3x^2 + 3xy/2 - 7xy^2/2
Step-by-step explanation:
So we know the perimeter is 20x^2 + xy - 7y^2,
To find any perimeter you need 2l + 2w = P so,
One of the sides is 7x^2 - xy
First plug in the values,
2(7x^2-xy) + 2w = 20x^2 + xy - 7y^2
Multiply,
14x^2-2xy + 2w = 20x^2 + xy - 7y^2
Subtract,
14x^2 - 2xy - 14x^2 + 2xy + 2w = 20x^2 + xy - 7y^2 - 14x^2 + 2xy
2w = 6x^2 + 3xy - 7y^2
w = 3x^2 + 3xy/2 - 7xy^2/2
