18. It is 18 because when you multiply 2x2 plus 4 x2 plus 2 x3 you get 4 plus 8 plus 6 = 18
Step-by-step explanation:
here is fig 15
x=36 (v.o.a are equal)
36+y=180
y=180-36=144
y=z=144 vertically
Multiply equation II by 2 and then add up the equations.
The answer is c because of y=mx+b
Answer:
ST = 12 units
Step-by-step explanation:
As RA is parallel to ET, the angle in R is equal to the angle in T, and the angle in A is equal to the angle in E, so the triangle RAS is similar to the triangle SET.
If RT is 21 units, we have that RS + ST = 21 -> RS = 21 - ST
Using a rule of three with the sides of the triangle (as they are proportional), we have:
RS / ST = AR / ET
(21 - ST) / ST = 6 / 8
4 * (21 - ST) = 3*ST
84 - 4*ST = 3*ST
7*ST = 84
ST = 12 units
