For the first equation, the answer is C) completing the square. For the second equation, the answer is B) zero product property.
For the first equation, we can easily complete the square by finding half of b and squaring it; then we can take the square root of both sides and solve the equation.
For the second equation, since it is already factored, we use the zero product property to solve it.
Let x = the number of students at Taft high school 5x-100 = the number of students at Jefferson high school if x =300 than 5(300)-100=1500-100=1400 students at Jefferson high school