Answer: 2730
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Explanation:
A shortcut way is to start at 15 and count down til you reach three values. So that means you'll have 15, 14, 13 which multiplies out to...
15*14*13 = 2730
Or you can use the nPr formula, with n = 15 and r = 2, to get the same answer
nPr = (n!)/((n-r)!)
15P3 = (15!)/((15-3)!)
15P3 = (15!)/(12!)
15P3 = (15*14*13*12!)/(12!)
15P3 = 15*14*13
15P3 = 2730
Well think about it. 70 mph then how long does it take to get to 70miles. An hour.. Just make it specific
1. Rewrite the system:
x+12y=68 (i)
x=8y-12 (ii)
2. Let's substitute the equation (ii) into the equation (i):
x+12y=68
(8y-12)+12y=68
3. Then, you have:
8y-12+12y=68
4. When you clear "y", you have:
20y-12=68
20y=68+12
20y=80
y=80/20
y=4
5. You already have the value of "y". Now, you must substitute this value into the equation (ii):
x=8y-12
x=8(4)-12
x=32-12
x=20
6. Therefore, the result is:
x=20
y=4
The distributive property combines (a single term) and (two or more terms) to make multiplying whole numbers simpler
hope this helps