It says that I should add fractions with unlike denominators.

If there are different denominators in a fraction you have to multiply the denominators by their least common factor(lcm).

Example:

2/4 + 5/8=

We can multiply the 4 and the 2 by 2 to get 4/8.

2/4= 4/8

Then, you add normally.

4/8+5/8= 9/8

And remember you cant add the denominator it stays the same, that is why we made them the same.

4 and 5)16.97 or 12√2

6)15.59 or 9√3

7)y = 15.59 or 9√3     x =27

8)17.80

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: