Answer:
x = -1 and x = 4
Step-by-step explanation:
Step 1: Get everything to one side of the equation so it's set equal to zero..
-x² + 4x = x - 4 becomes...
-x² + 3x + 4 = 0 (subtract x and add 4 to both sides)
x² - 3x - 4 = 0 (divide both sides by -1, we want the x² term to be positive)
(x - 4)(x + 1) = 0 (factor)
so
x - 4 = 0, then x = 4
and
x + 1 = 0, then x = -1
The left side of the equal sign is exactly the same as the right side, so it has infinitely many solutions.
Answer:
3/8
Step-by-step explanation:
F(8)=24/8^2=24/(8*8)=24/64=3/8
Total number of sheets are 12.
Total number of white sheets= 9
Total number of red sheets = 3
Probability = Number of favorable outcomes/ total number of outcomes.
Hence
When Calvin throws the sheets in the air, the probability that he gets a white sheet is

which equals to 
that becomes 0.75