I'll solve 21, and you then should be able to solve the rest on your own!
Since ADC is 135, that means that that whole angle is 135 degrees. In addition, since angles ADB and BDC add up to ADC, we get ADB+BDC=ADC=135=11x+9+7x=18x+9. Subtracting 9 from both sides, we get 126=18x. Dividing both sides by 18, we get x=7. Plugging that into 11x+9=BDC, we get 11*7+9=77+9=86
Anxiety can cause you to overthink what you already know which interns makes you think you don’t know it. Math is just formulas and arthritic and if anxiety has you doubting that you know how to solve a problem then you won’t remember how to solve it
Answer:
ummm where is the question anyway?
Answer:

Step-by-step explanation:
Given
Square

Triangle


Required
Find h, if both shapes have the same area
The area of the square is:


The area of the triangle is:


Equate both areas

Divide both sides by x

Multiply both sides by 2



B. 361/4
you get: x^2-19x+361/4=(x-19/2)^2