H²+10h+21 = 0
h²+3h+7h+21 = 0
h(h+3)+7(h+3) = 0
(h+3)(h+7) = 0
h+3=0
h = -3
h+7=0
h=-7
While I'm unsure what the word choices were, his claim is likely to be true.
Since he claims the probability of heads is 40%, that should be what we see in an experiment. 0.38 is very close to 0.40, or 40%, so this is true. Therefore his claim is likely to be true, and the probability of tails should be about 60%.
He sold 12 coins, 16+28+32+4=80. 15% of 80 is 12
ANSWER
x coordinates of the intersection points
EXPLANATION
The given system of equations is:


We want to use the graph of these functions to solve

The point of the intersection of the graph gives the solution to the simultaneous equation above.
Hence the x-coordinates of the intersection points gives the solution set of

The last choice is correct.
1 batch need 3/4 gallon of milk
She has 1/4 gallon cup
(3/4) divided by (1/4)
A technique in math is just flip the divider which is (1/4) to (4/1)
so it becomes (3/4) multiply (4/1) = (3x4) / (4x1) = 12/4 = 3 times for one batch
She needs three batches so 3 x 3 = 9 times to fill the measuring cup to make all 3 batches of milkshake.