complementary angles sum up to 90°.
so if one of them is 43°, then the other is just 90 - 43 = 47°.
Carry out the mult.: f(x) = -[x^2 - 21x + 9x - 189]
Combine like terms: f(x) = -[x^2 - 12x - 189]
Eliminate the brackets [ ]: f(x) = -x^2 + 12x + 189
Identify coefficients a, b and c: a= -1, b=12, c=189
The equation of the axis of symmetry is x = -b/(2a), which here equals
x = -(12)/[2(-1)], or x = 6
This is also the x-coordinate of the vertex. Plug x=6 into the original equation to calculate the y-coordinate.
Divide the volume by the two measures. 728 ÷ 8 = 91 ÷ 6.5 = 14 so, the shoe box is we inches long.
Credit card A, because it's effective interest rate is about 0.09 LESS THAN that of credit card B.
