The answer 7980 divided by .19 =/is 42.
Answer: 21
Step-by-step explanation:
5%x420= 21
To see how they are related, let us solve the two equations.
FIRST EQUATION



SECOND EQUATION



Hence the solutions to the two equations are ADDITIVE INVERSE of each other.
The formula for slope is 
In this case:

so...


-1 <<<The slope
Hope this helped!
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