Let x = your number.
x^2 - 21 = 4x. Subtract 4x from both sides.
x^2 - 4x - 21 = 0. Factor.
(x - 7) (x + 3) = 0. Set each term to 0.
x + 3 = 0. Subtract 3 from both sides.
x = -3. This is the negative solution.
Set the other term equal to zero.
x - 7 = 0. Add 7 to each side.
x = 7. This is the positive solution.
Answer:
Hardness.
Step-by-step explanation:
A mineral's hardness is a measure of its relative resistance to scratching, measured by scratching the mineral against another substance of known hardness on the Mohs Hardness Scale.
Hey There!
In order to simplify this expression, you would have to combine the like terms.
9+1 = 10
Nothing else could be done, therefore the answer would be.
7v + 10
Hope this helped!
Oh yeah sweetie no I’m not here for church I just got a text message I don’t think I can
