Answer:
Step-by-step explanation:
3+x-3= - 5x
combine like terms
3 += 4
x -5x = -4x
then combine 4 and -4x
Answer:
162.4 in²
Step-by-step explanation:
LETS GET INTOOOOEEETTT
Let's start with what we know:
Area of regular octagon = 1/2 x perimeter x apothem
We know the apothem, so all that we need to find to fill in the above equation is the perimeter:
perimeter = 8 x 5.8 = 46.4in
Now we can fill in our original equation and solve:
Area of regular octagon = 1/2 x perimeter x apothem
Formula = n (s/2)² divided by tan( π /n)
= 8 (5.8/2)² divided by tan ( π /8)
= 162.4283 in²
ORRR when rounded to the nearest tenth,
=162.4 in²
X + 5 + 11x = 12x + y
Simplify: 12x + 5 = 12x + y (We are adding x and 11x on the left side)
Subtract 12x from each side makes each zero.
5 = y
So we can plug in and test. I'm picking two random numbers to plug in for x. 10, and 82
x = 10, y = 5
10 + 5 + 11(10) = 12(10) + 5
125 = 125
x = 82, y = 5
82 + 5 + 11(82) = 12(82) + 5
989 = 989
So we verified y = 5
Answer:
Step-by-step explanation:
3×8-2×3=18
Answer:
x = 14
Step-by-step explanation:
Extend line AB so that it intersects ray CE at point G. Then angles BGC and BAD are "alternate interior angles", hence congruent.
The angle at B is exterior to triangle BCG, and is equal to the sum of the interior angles at C and G:
138 = (376 -23x) +(x^2 -8x)
Subtracting 138 and collecting terms we have ...
x^2 -31x +238 = 0
For your calculator, a=1, b=-31, c=238.
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<em>Additional comment</em>
You will find that the solutions to this are x = {14, 17}. You will also find that angle BCE will have corresponding values of 54° and -15°. That is, the solution x=17 is "extraneous." It is a solution to the equation, but not to the problem.
For x=14, the marked angles are A = 84°, C = 54°.