Sorry, it's late, and I'm a bad explainer.
The error is adding (2x-12) with x and 30. This is wrong because you are adding the angles inside the triangle and you are assuming that (2x - 12) is the unlabeled angle INSIDE the triangle, when it is the exterior angle/outside of the triangle.
A straight line is also 180°.
(2x - 12) + ? = 180
30 + x + ? = 180
If you look at the equations, and put parentheses around 30 + x, (30 + x) and (2x - 12) should be the SAME NUMBER. So you could set them equal to each other to find x. (or you could also look at the picture and see that they both need/are missing the same angle)
2x - 12 = 30 + x
x = 42
Now you plug 42 into the exterior angle equation
2(42) - 12 = 84 - 12 = 72°
The answer is 1x10^2 or just simply 10^2.
Answer:
0
Step-by-step explanation:
2a+ 2/a =4
Multiply each side by a to clear the fraction
a( 2a+ 2/a) =4*a
Distribute
2a^2 +2 = 4a
Subtract 4a from each side
2a^2 -4a +2 = 4a-4a
2a^2 -4a +2 =0
Divide by 2
2/2 a^2 -4a/2 +2/2 =0/2
a^2 -2a +1=0
Factor
(a-1) (a-1) =0
Using the zero product property
a=1
2a^2 -2/a^2
2(1)^2 -2/1^2
2-2
0
Solve for x: x^2+4x-5=16x
first take 16x from both sides of the equation
x²-12x-5=0
now we have a quadratic. we can solve it by using the quadratic formula
x=-b plus or minus the square root of b²-4ac all divided by 2a
where a=1, b=-12 and c=-5
plug these numbers into the formula
x=12 plus or minus the square root of 144-4x1x-5 all divided by 2
<span>x=12 plus or minus the square root of 164 all divided by 2
or in decimal form </span>x = {12.403124237, -0.403124237}