Answer:

<u>Explanation</u>:

<u>Given:</u>
<u>using this formula:</u>



Answer:
multiplication
Step-by-step explanation:
The answer is r=-3. You use the distributive property which is basically multiplying -8 with all the numbers inside the parenthesis. So -8 x r and -8 x -2. This results to -8r+16=40 (Two negative numbers multiplied together will form a positive number). We use inverse operations to subtract 16 from both sides. 16-16 is 0 and 40-16 is 24. So we are left with -8r=24. We want to be left with only r, so we once again use inverse operations to divide -8 from both sides. -8/-8 is 1, and 24/-8 is -3. So we end up with r=-3. Hope this helped :]
Y=(kx)/z
15=(k10)/4
15=(5k/2)
15=k(5/2)
ties both sides by 2/5 to clear fraction
6=k
y=(6x)/z
x=20
z=6
y=(6*20)/6
y=20
The answer is -9 + 9i. Hope this helped.