Answer:
D
Step-by-step explanation:
The basic equation to solve this would be D = RT, which is
D is Distance
R is Rate (speed)
T is time
To find total distance D, we can find individual distances for two legs of the whole.
First Leg:
R = 8
T = a
D = 8a
Second Leg:
R = 7.5
T = b
D = 7.5b
Total distance D is:
D = 8a + 7.5b
Moreover, we know student runs 45 minutes in total hence a + b = 45 or we can say a = 45 - b, so we can replace this in the equation found:
D = 8a + 7.5b
D = 8(45 - b) + 7.5b
Answer choice D is right.
Answer:
-53
Step-by-step explanation:
If x=3 and y=-4
Plug the numbers into the equation
3 - (-4) - 3 + (-57)
Now solve the equation right to left
3 - (-4) = 7
7 - 3 = 4
4 - 57 = -53
So the answer is -53
Answer:
first is -3, second number is 0
Step-by-step explanation:
you have two equations x+3=y and 4*x+12=5*y
Use the first one and write y in terms of x in the second equation:
4*x+12=5*(x+3)
4*x+12=5*x+15
12=5*x-4*x+15
12=x+15
x=-3
Answer:
4, 6, 63, 10
Step-by-step explanation:
gets mutiplied by 7
B and C for sure maybe A. Def not D