Answer: Choice B
They did not perform the cross multiplication properly
The correct step should be m*24 = 8*15 which solves to m = 5
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Explanation:
In general, if we had the equation A/B = C/D, then it cross multiplies to A*D = B*C. We refer to this as cross multiplication because of the shape made when we connect the terms (to figure out what multiplies with what). The diagram below shows what I mean.
So that's why m/8 = 15/24 cross multiplies to m*24 = 8*15
Simplifying things a bit leads to 24m = 120. Then we divide both sides by 24 to fully isolate m and we get m = 120/24 = 5. Therefore, m = 5.
the answer is b because x is greater than or equal to 0
Answer:
x = 112
Step-by-step explanation:
We can create two equations 1. one that calculates calories burned and 2.another that calculates minutes:
20*x + 5*y = 1200
x + y = 120
Then we can solve for x
x = 120 - y
then we can plug that into the top equation:
20(120 - y) + 5y = 1200
divide by 5:
4(120 - y) + y = 240
distribute:
480 - 4y + y = 240
and then do all that combining like factors what not and simplify and solve:
480 - 3y = 240
-3y = -240
y = 8
NOW WE CAN JUST PLUG IN THE ANSWER FOR Y TO FIND X
8+x =120
x = 112
As the fraction it would be 72/100
Answer:
x = ±11
Step-by-step explanation:
x^2 =121
Take the square root of each side
sqrt(x^2) = ±sqrt(121)
x = ±11
