Answer:
1 hour
Step-by-step explanation:
Hello, let's say that her departure trip takes t in minutes, as her return speed is 3 times her departure speed, she took t/3 for the return and we know that this 40 minutes less, so we can write.
t/3=t-40
We can multiply by 3
t = 3t -40*3 = 3t - 120
This is equivalent to
3t -120 = t
We subtract t
2t-120 = 0
2t = 120
We divide by 2
t = 120/2 = 60
So this is 60 minutes = 1 hour.
Thank you.
Estimation:
23 --> rounded to 20
71 --> rounded to 70
70 + 20 = 90. I rounded both numbers down so the exact sum must be only a little greater than my estimate.
Y = kx is the direct variation equation
Substitute the x and y that are given to find k then write your new equation in terms of y with the k.
288 = k(16) divide by 16 to find k
18 = k
Now write the new equation
y = 18x
y = 18(13) or y = 18(-13) I'm not sure by what you have typed if that is supposed to be and equal sign or a negative.
y = 234 OR y = -234
Answer: t = 29.5 inches
Step-by-step explanation:
Given that the ΔSTU, u = 23 inches, ∠T=158° and ∠U=17°.
We can Find the length of t by using sine rule
t/saint = u/sinU
t/sin158 = 23/sin17
t = sin158 × 23/sin17
t = 29.47 inches
t = 29.5 inches