Answer:
24
Step-by-step explanation:
18/n = 21/28 You can cancel, but calculators make that unnecessary. Cross multiply
21n = 18 * 28
21n = 504 Divide by 21
n = 504 / 21
n = 24
==================
12/16 = n / 64 Cross Multiply
16n = 12 * 64
16n = 768 Divide by 16
n = 768/16
n = 48
Answer:
Step-by-step explanation:
we have
E------>the number of sit-ups
m----> the time in minutes
S----> the number of sit-ups after drinking the sports drink
----> equation A
----> equation B
substitute the equation A in the equation B
Like terms are terms whose variables are the same. In this case, 7 and 2 have no coefficients therefore are like terms. For example, 7x and 2x would both be like terms because they have the same coefficient which is x.
You can just do the inverse operation. 39 divied by 10 = 3.9
so 3.9 *10 =39
hope it helped
Answer:
x=-3, x=1, x=8
Step-by-step explanation:
When you have to find the zero of an equation like (x+3) all you have to do is solve for x.
x+3=0 equal the equation to zero
x+3-3=0-3 cancel out 3
x=-3 answer
If you have to find the zero of an equation like f(x)=-2x^2 - 5x + 7 then you would have to factor the equation.
7*-2=-14 multiply
-7 & 2 find the two numbers that when multiplied =14 and when added = -5
(2x^2 + 2) (-7x + 7) replace -5 with -7 & 2
-2x (x - 1) -7 (x - 1) factor
(x - 1) (-2x - 7) rewrite
1st: x - 1 = 0
x = 1 : Answer
2nd: -2x - 7= 0
-2x - 7 + 7 = 0 + 7
-2x = 7
-2x / -2 = 7 / -2
x = 7 / -2 : Answer