77(7) = 539, the total points of all her tests
539 - 18 + 81 = correct total points = 602
602/7 = 86 which is the new average
Sure this question comes with a set of answer choices.
Anyhow, I can help you by determining one equation that can be solved to determine the value of a in the equation.
Since, the two zeros are - 4 and 2, you know that the equation can be factored as the product of (x + 4) and ( x - 2) times a constant. This is, the equation has the form:
y = a(x + 4)(x - 2)
Now, since the point (6,10) belongs to the parabola, you can replace those coordintates to get:
10 = a (6 + 4) (6 - 2)
Therefore, any of these equivalent equations can be solved to determine the value of a:
10 = a 6 + 40) (6 -2)
10 = a (10)(4)
10 = 40a
Answer: 500 chicken feed and 200 careful calculators
Step-by-step explanation:
2x+3y=1,600
40x+50y=30,000
those are your first two equations
your first matrix equation for A is 2, 3,40,50 and B is 1,600 and 30,000 when you enter those in your calculator and 500 and 200 should be your result.
Answer: See below
Step-by-step explanation:
When you see that something is to the power of a negative number, it is another way of saying 1 over.

Plug x and y when you type in the calculator
2-2(2+3) and see your answer