Answer:
Ans =C(4,1),(-4,1),(4,6),(-4,6)
The square of a binomial expands as follows:

Expanding all the binomials, we have

Sum like terms:

Simplify terms appearing on both sides:

Move all terms involving k to the left and all numbers to the right:

Divide both sides by -20:

Answer:
280 hours
Step-by-step explanation:
Amount paid + profit = cost of a lesson per hour
$2000 + $5000 = $25(h)
7000 = 25h
7000/25 = h
280 = h
An angle bisector is a line or ray that divides an angle in half
1) Never heard of someone referring to the Law of Levers before, must be showing my age. A system as you describe is at equilibrium when the net torque is equal to zero. Since torque is Fr=mgr so for this system we have a sum of:
27g*10+30g*x=0 The sum must be zero to be at equilibrium, dividing both sides by g you have:
270+30x=0
270=-30x
x=-9
The negative just indicates that the magnitude of 9 is on the opposite side of the fulcrum, so x=9ft in magnitude.
2) Inverse variation is of the form y=k/x, in this case we are given a point so we can solve for the constant, k, of variation...
y=k/x, and we are given y=-12 when x=5 so
-12=k/5
k=-60 so the equation is:
y=-60/x which can be expressed as
xy=-60