Answer:
17 - 42
18 - 50
Explanation:
17)
You know the total measurement of both angles is 180.
So your formula is (2x+54) + x = 180. Now rearrange to get
180 - (2x+54) = x or 180-2x+54 =x
Simply to -2x+126 = x followed by moving x and moving 126 to get
-3x = -126 , now divide both sides by -3
18)
Your complete circle is 360 and you know one angle is 90.
Set your formula to 360=90+(3x)+(x-20)+(2x-10)
Rewrite to 360 = 90+3x+x-20+2x-10 and combine like terms
360 = 90 - 20 - 10 + 3x + x+2x
360 = 60 + 6x
360 - 60 = 6x
300 = 6x
300/6 = x
50 = x