Answer:
#4
Verify if sides are proportional:
XW/XV = XY/XZ
- 15/(15 + 20) = 27/(27 + 36)
- 15/35 = 27/ 63
- 3/7 = 3/7
∠X is common and included, the side ratios are same.
ΔXZV ~ ΔXYW by SAS
#5
Verify side ratios are equal, from least to greatest:
- ML/QR = 10.5/7 = 1.5
- LN/PR = 12/8 = 1.5
- MN/PQ = 18/12 = 1.5
Since ratios are same, the triangles are similar by SSS
#2
Ratio of corresponding sides:
(x + 2)/3 = 10/(x + 1) = 8/4
- x + 2 = 6 ⇒ x = 4
- x + 1 = 5 ⇒ x = 4
#3
Ratio of corresponding sides:
18/3x = (x + 1)/15 = 9/13.5
- 6/x = 2/3 ⇒ x = 9
- (x + 1)/15 = 2/3 ⇒ x + 1 = 10 ⇒ x = 9
