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3 years ago

3x-4 or = to 7 plz help

Mathematics

2 answers:

pogonyaev3 years ago

7 0

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.

Step-by-step explanation:

lisabon 2012 [21]3 years ago

3 0

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.

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VashaNatasha [74]

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3 years ago

Big Bob’s Pizza is having a special on pizza and is offering two different choices: Choice #1: One slice of pizza from a pizza w

olya-2409 [2.1K]

<h2>Answer:</h2>

Choice #1 is better

<h2>Step-by-step explanation:</h2>

To find the solution to this problem, we have to compute the are in each case, and divide each value by the corresponding cost in order to find the cost per square. The lower the cost, the better the offer because it will give you more pizza for your money Thus:

CHOICE 1:

Here the offer of Big Bob’s Pizza gives one slice of pizza from a pizza with a 22 inches diameter (then the radius is 11 inches) and is cut into 8 slices, so the area for the first entire pizza is:

$A_{1}=\pi r^2=\pi(11)^2 \\ \\ A_{1}=121 \pi in^2$

Each slice has an area of:

$A_{slice}=\frac{121 \pi}{8} \\ \\ A_{slice}=47.51in^2$

Finally, the cost per square inch is:

$C=\frac{4.95\$}{47.51in^2}=0.10\$$

CHOICE 2:

Here the offer of Big Bob’s Pizza gives: An entire personal-size pizza that has a diameter of 6 inches (then the radius is 3 inches), so the area for the entire pizza is:

$A_{2}=\pi r^2=\pi(3)^2 \\ \\ A_{2}=28.27 in^2$