See the picture attached to better understand the problem
we know that
(x+20)+∠1=180°-------> by supplementary angles
∠1=160°-x
∠1+∠2=180°--------> by supplementary angles
∠2=180-(160-x)-----> ∠2=20+x
∠2=80°------> by corresponding angles
so
20+x=80
x=80-20-------> x=60°
the answer is60°
Answer:
40 and a half
Step-by-step explanation:
Divide 486 by 12.
12 goes into 486 40 whole times.
2x + 6 = -2x - 2 equation
X = -2 solution
Answer:
Step-by-step explanation:
Let 
Subbing in:
a = 9, b = -2, c = -7
The product of a and c is the aboslute value of -63, so a*c = 63. We need 2 factors of 63 that will add to give us -2. The factors of 63 are {1, 63}, (3, 21}, {7, 9}. It looks like the combination of -9 and +7 will work because -9 + 7 = -2. Plug in accordingly:
Group together in groups of 2:
Now factor out what's common within each set of parenthesis:
We know this combination "works" because the terms inside the parenthesis are identical. We can now factor those out and what's left goes together in another set of parenthesis:
Remember that 
so we sub back in and continue to factor. This was originally a fourth degree polynomial; that means we have 4 solutions.
The first two solutions are found withing the first set of parenthesis and the second two are found in other set of parenthesis. Factoring 
gives us that x = 1 and -1. The other set is a bit more tricky. If
then
and
You cannot take the square root of a negative number without allowing for the imaginary component, i, so we do that:
±
which will simplify down to
±
Those are the 4 solutions to the quartic equation.
Perimiter=2(L+W)
L=2x
W=4x-1
P=2(2x+4x-1)
P=2(6x-1)
P=12x-2
