Answer:
3 + 4 = 7 which is true.
Step-by-step explanation:
Whenever you have an equation with a plain variable (that is, no exponent included), there is only one number that will work when substituted for x.
To solve it, you have to "undo" what is done to the variable. You also go in the reverse order of operations, so you do the addition/subtract first, then multiplication/division.
You also have to do the same to both sides, kind of like keeping a balance scale in balance.
In this case, we subtract 4 from both sides first:
3x + 4 -4 = 7 - 4
The + 4 - 4 cancel each other out, so you get:
3x = 3
3x means "3 times x" so you divide by 3 to undo it. I will use the / to indicate division:
3x / 3 = 3 /3
so 1x = 1.
Since 1x is "1 times x" it is the same as x by itself, so:
x=1
AND, if we substitute 1 back into the original equation (the asterisk stands for multiply):
3 * 1 + 4 = 7
3 * 1 is 3, so:
3 + 4 = 7 which is true.
1 is the only number that works.
Hope this helped.
Answer: The copy machine makes 171 copies in 4 minutes and 45 seconds.
Step-by-step explanation:
Let's dissect the question. The copy machine makes 36 copies per minute.
36 per min.
To see how many copies it makes in 4 minutes and 45 seconds, we multiply 36 * 4.75. 45 seconds is 3/4ths of a minute, or 0.75 of a minute.
It makes 171 copies in 4 minutes and 45 seconds.
Evaluate a^2 where a = -5:
a^2 = (-5)^2
Hint: | Evaluate (-5)^2.
(-5)^2 = 25:
Answer: 25
Answer: you just sech in google what is bla bla bla (don't do that ) XD
Step-by-step explanation:
Answer:
sample variances
Step-by-step explanation:
The pooled variance method is used to estimate the variance of several different population with different means, but are assume to have the same variance.
The weights represent the sample variances.
So the correct answer is
sample variances
