A student says that the zeros of the quadratic equation y = x2 – 10x + 21 are -3 and - 7. Is the student correct? If not, describe and correct the error the
student made.

No, x=3 x=7

Step-by-step explanation:

x²-10x+21 = 0

Step 1: Factor left side of equation.

(x−3)(x−7)=0

Step 2: Set factors equal to 0.

x−3=0 or x−7=0

x=3 or x=7

step-by-step explanation:

12: 00 p.m. to 7: 00 p.m. is a total of 7 hours.

4: 00 p.m. to 7: 00 p.m. is a total of 3 hours.

this means that from 4: 00 p.m to 7: 00 p.m. this represents 3/7 of what was lost from 12: 00 p.m. to 7: 00 p.m.

after knowing this, after doing 11,600 - 6,800 = 4,800

4,800 represents 3/7 of what was lost for 7 hours.

we then divide 4,800 by 3 which gets 1,600.

because we know that 1,600 represents 1/7 of how much water was lost, we just have to multiply by 7, which gets 11,200.   after adding 11,200 to how much water was left at 7: 00 p.m. which was 6,800. 11,200 + 6,800 = 18,000

this means that the pool originally had 18,000 gallons in the pool.

you can also check your work by doing 18,000 - 4(1600), which becomes           1800 - 6400 which gets you 11,600.

answer: what statements

step-by-step explanation if you write the statements down then i could you.