Answer:
-6x+12
-9+5a
7x+63
8y-4/5x-12
Step-by-step explanation:
To solve these all you have to do is take the number outside of the parenthesis and multiply them by each term.
-3(2x)-3(-4) All I did here was expand the problem to show what i mean by terms.
-6x+12
Do this for each problem.
0.1(-90)+0.1(50a)
-9+5a
-7(-x)-7(-9) For this one you are taking negatives times negatives so each answer will be positive.
7x+63
4/5(10y)+4/5(-x)+4/5(-15)
8y-4/5x-12
The formula for the discriminant is b^2-4ac. The formula you wote is in the form of
ax^2+c=0, so first, you need to bring that -2 to the left. When you do that, you get (the original equation would be ax^2+bx+c but you have no bx.)
3x^2-8
So, since there's no b, it would be
b^2-4ac
0^2-4(3)(-8
-12 x -8
96
The answer to your question is -3 !!
We could write the fractions as decimals.

The answer is
.004 or 4/1000.