Answer:
Adding 5 from both sides then dividing by 7
Step-by-step explanation:
The best way to isolate x is to add 5 to both sides first:
21 = 7x
Then to isolate x by itself divide both sides by 7
x = 3
That would be the value of x and your final answer.
We need to call for x minute
+ Phone Company A charges a monthly fee of $42.50, and $0.02 for each minute talk time. So we have to spend: <span>$42.50+ $0.02x
+ </span>Phone company B charges a monthly fee of $25.00, and $0.09 for each minute of talk time. So we have to spend: <span>$25.00+ $0.09x
We solve for x: </span>$42.50+ $0.02x> <span>$25.00+ $0.09x
or </span>$42.50- $25.00 > $0.09x- <span>$0.02x
and we have $0.07x<$27.50
or x< 27.50:0.07 and x< 393.86
The answer is:
If we have to call much time, at least 394 minutes, we should choose A
If not, choose B</span>
Answer: see proof below
<u>Step-by-step explanation:</u>

Answer:
61 , 63 , 65 , 67
Step-by-step explanation:
Let the least even number be denoted by x. The sum of the four consecutive even numbers would be:
(x) + (x + 2) + (x + 4) (x + 6) = 256
First, simplify. Combine all like terms:
x + x + x + x + 2 + 4 + 6 = 256
4x + 12 = 256
Isolate the variable, x. Note the equal sign, what you do to one side, you do to the other. Do the opposite of PEMDAS.
First, subtract 12 from both sides of the equation:
4x + 12 (-12) = 256 (-12)
4x = 256 - 12
4x = 144
Next, divide 4 from both sides of the equation:
(4x)/4 = (144)/4
x = 144/4
x = 61
61 is your first number. Find the next 3 consecutive numbers:
x = 61
x + 2 = 63
x + 4 = 65
x + 6 = 67
Check:
61 + 63 + 65 + 67 = 256
256 = 256
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