10.
Answer: 42° and 138°
Steps: First find value of x by adding both equations and setting them equal to 180°:
3x + 12x - 30 = 180
15x - 30 = 180
15x = 210
x = 14
Next, put value of x into equations to find the angle:
3x
3(14)
42°
12x - 30
12(14) - 30
168 - 30
138°
11. Answer: 28°
Steps: Complementary angles add up to 90°, so subtract 62° from 90° to find its complementary angle.
90 - 62 = 28
12. Answer: Corresponding angles are congruent.
AOB = 2 . x
2x = 60°
x = 30°
You add of the sides to get the perimeter.. 9 plus 9 is 18 and 5 plus 5 is 10. 10 plus 18 of 28. The perimeter of ABCD is 28.
I hope this helps.
When negative five is subtracted from a number the result is 10. The number is 5.
x - (-5) = 10
x + 5 = 10
x = 10 - 5
x = 5
First you distribute 4 to 2x and 3. Then after you do that you get 8x+12=10x