7x -7x=84 (i don't need step-by-step, i just need what x equals)

Note the equal sign. What you do to one side, you do to the other.

First, combine like terms

-7x + -7x = -14x

-14x = 84

Isolate the x. Divide -14 from both sides

(-14x)/-14 = (84)/-14

x = 84/-14

Divide

x = -6

-6 is your answer for x

~Rise Above the Ordinary, Senpai

to find the unit price, we must figure out the cost of one item (in this case one dish towel).   to do this, we divide the total price ($7.92) by the number of items bought (for this problem it is 8, because there are eight dish towels in one pack).  

$7.92/8 = $0.99

therefore, the unit price, or the price of one dish towel, is $0.99.

hope this !

explanation:

infrared radiation has wavelength in the range between 700 nm and 1 mm. lets' convert these values into scientific notation, keeping in mind that:

let's start from the lower value, we have:

(we moved the dot two places to the left, so we increased the exponent by 2 units, from -9 to -7)

the higher value is:

so, the range of wavelength of infrared radiation is: