Answer:
x = 2.2
Step-by-step explanation:
-0.45x + 0.33 = -0.66
Subtract .33 from each side
-0.45x + 0.33-.33 = -0.66-.33
-.45x = -.99
Divide each side by -.45
-.45x./-.45 = -.99/-.45
x = 11/5
x = 2.2
1/9 - (-2/5 - 8/9) = 1/9 + 2/5 + 8/9 = 1 + 2/5 = 7/5 or 1 2/5
X² + 3x = 10
Convert to standard form.
x² + 3x - 10 = 0
factor x² = x * x
factor -10 = 5 * -2
(x + 5) (x - 2) = 0
x(x -2) + 5(x-2) = 0
x² - 2x + 5x - 10 = 0
x² + 3x - 10 = 0
x + 5 = 0 x² + 3x = 10
x = -5 -5² + 3(-5) = 10
25 - 15 = 10
10 = 10
x - 2 = 0 x² + 3x = 10
x = 2 2² + 3(2) = 10
4 + 6 = 10
10 = 10
Subtract 7.8 points by 4.8 and you get 3.4 !!