Let A represent the speed of car A. Using your formula,
.. A*2 = D
.. (A +15)*1.5 = D . . . . . the same distance in a shorter time at a higher speed
Equating the two expressions for D, we get
.. 2A = 1.5(A +15)
.. 2A = 1.5A +22.5 . . . . . eliminate parentheses
.. 0.5A = 22.5 . . . . . . . . .subtract 1.5A
.. A = 22.5/0.5 = 45 . . . .divide by 0.5
Car B was 15 mph faster than this.
Car B traveled at 60 miles per hour.
Answer:
y = -6x + 30
Step-by-step explanation:
The inicial value you have is $30, so this will be the value of y after 0 weeks, that is, x = 0
After one week, you spend $6, so you will have y = 30 - 6 = 24 when x = 1.
With these pair of values, we can find the linear equation:
y = ax + b
for x = 0, y = 30:
30 = a*0 + b
b = 30
for x = 1, y = 24:
24 = a*1 + 30
a = 24 - 30 = -6
So, our equation is:
y = -6x + 30
Answer:
Point 1 to the left with a closed circle <-----*
Point 8 to the right with an open circle o------>
Step-by-step explanation:
Got the answer correct
Answer:
the solution of the system is:
x = 1 and y = 2.
Step-by-step explanation:
I suppose that we want to solve the equation:
-6*x + 6*y = 6
6*x + 3*y = 12
To solve this, we first need to isolate one of the variables in one of the equations.
Let's isolate y in the first equation:
6*y = 6 + 6*x
y = (6 + 6*x)/6
y = 6/6 + (6*x)/6
y = 1 + x
Now we can replace this in the other equation:
6*x + 3*(1 + x) = 12
6*x + 3 + 3*x = 12
9*x + 3 = 12
9*x = 12 - 3 = 9
x = 9/9 = 1
Now that we know that x = 1, we can replace this in the equation "y = 1 + x" to find the value of y.
y = 1 + (1) = 2
Then the solution of the system is:
x = 1 and y = 2.
<h3>
Answer: 20% increase</h3>
======================================================
Explanation:
A = old value = 110
B = new value = 132
C = percent change
C = 100*(B-A)/A
C = 100*(132-110)/110
C = 20%
The positive C value means we have a percent increase, which corresponds to the fact that A = 110 increases to B = 132.
The B-A = 132-110 = 22 portion up top indicates that the increase is 22 pounds, which when divided over 110, gets us 22/110 = 0.20 = 20%
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Checking the answer:
20% of 110 = 0.20*110 = 22
She's able to lift 22 extra pounds on top of the 110 pounds she can handle previously, so she can now lift 110+22 = 132 pounds. The answer is confirmed.
