Answer: a. y=5
b. RS = 37 , ST =16 and RT = 53 .
Step-by-step explanation:
Given: On number line we have,
RS = 7y + 2, ST = 2y +6, and RT = 13y - 12.
a. Since its on number line so we have
RT = RS+ ST
i.e. 13y - 12 = (7y + 2) + ( 2y +6)
⇒ 13y - 12 = 7y + 2 + 2y +6
⇒ 13y-12 = 9y+8
⇒ 13y-9y = 8+ 12 [Subtract 9y from both sides and add 12 in both sides]
⇒ 4y = 20
⇒ y= 5 [Divide both sides by 4 ]
b. Now , RS = 7(5) + 2 = 35+2= 37,
ST = 2y +6 = 2 (5)+6 = 10+6 =16,
and RT = 13y - 12 = 13 (5)-12 = 65-12 = 53.
Hence, RS = 37 , ST =16 and RT = 53 .