∆PQR and ∆SQT are similar, so corresponding sides occur in fixed ratios with one another. This means
SQ / PQ = ST / PR
Solve for x :
8 / ((x + 5) + 8) = (x - 9) / 21
8 / (x + 13) = (x - 9) / 21
168 = (x - 9) (x + 13)
168 = x² + 4x - 117
x² + 4x - 285 = 0
(x + 19) (x - 15) = 0
⇒ x = -19 or x = 15
But x can't be smaller than 9, otherwise ST = x - 9 would be a negative length. So x = 15.
Answer:
Zero Product Property
Step-by-step explanation:
The zero product property states that anything multiplied by 0 is 0.
Answer:
10 km/hr
Step-by-step explanation:
Average speed = Total distance travelled / Total time taken
Ardi:
Total distance travelled = 70 km
Total time taken = 35 minutes = 35/60 hour
Average speed = Total distance travelled / Total time taken
= 70 km ÷ 35/60 hr
= 70 × 60/35
= 4,200/35
= 120 km/hr
Lei:
Total distance travelled = 585 km Total time taken = 9:05 - 13:35 = 4 hours 30 minutes
= 4.5 hours
Average speed = Total distance travelled / Total time taken
= 585 km / 4.5 hours
= 130 km/hr
Difference, in km/h, between the average speed of their trains = Lei's train - Ardi's train
= 130 km/hr - 120 km/hr
= 10 km/hr
