Rock musician Donny West is paid 15% on his tour video online sales. Last year fans downloaded his songs 991,000 times, and he also sold 550, 000 videos. The songs are downloaded for $1.09 each and the videos were downloaded for $9 each. a. What was the total monetary amount of song downloads? b. What was the total monetary amount of video downloads? C. What was the combined total value of song and video downloads? d. How much did Donny West receive in royalties last year?

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4

x² + 3x + 7 = 0       [ax² + bx + c]

a = 1

b = 3

c = 7

quadratic formula:

    (+/- is this ±)

plug in the numbers into the variables

your answer is a