Answer:
D. 80x + 70 = 390
Step-by-step explanation:
80 times x (the degrees it heats up per minute times the number of minutes) + 70 (the degrees the oven was already at) = 390 (the number of degrees the oven needs to preheat to.)
This is the only answer that makes sense.
Hope this helps! :D
Also, where can I buy an oven that heats up this fast? XD
Answer:
10/6
Step-by-step explanation:
5:3
20:12 (get this by multplying 4)
10/6 (get this by multiplying 2)
Distance = rate*time
distance/time = rate
The race course is 3 miles around and Jeff does it twice, so the distance he goes = 2*3 miles = 6 miles.
He takes 20 minutes to go around once and 25 minutes to go around the second time, so the total time = 20 min + 25 min = 45 min.
His speed is miles per hour, not miles per minute, so convert 45 minutes to a hours:
45 min/60 min = 0.75 hours <span>distance/time = rate = 6 miles/0.75 hours = 8 mph</span>
Answer:
b = -9
Step-by-step explanation:
The function is given as :

The axis of symmetry for this function is x = 3/2
It is required to find the value of b. The axis of symmetry of a parabola is a vertical line that intercepts its vertex at its horizontal coordinate. It can be given by :

Putting x = 3/2 and a = 3 we get :

So, the value of b is -9.