Work shown above! Answer is D hope this helps c:
Slope intercepts do.
Linear equations are straight lines, not curves.
Solution sets are for inequalities.
Linear equations never have a squared value, that would make it exponential.
X^2 - 10x - 9 = 0
first we will move the constant term to the other side
x^2 - 10x = 9
then, to both sides we will add the number that makes the polynomial on the left a perfect square trinomial. Take half of the coefficient of x, then square it. half of the coefficient of x (-10) is -5, and -5 squared is 25. so:
x^2 - 10x + 25 = 34
factor the perfect square trinomial
(x - 5)^2 = 34
x - 5 = plus or minus sqrt(34)
x = 5 plus or minus sqrt(34)
X - unit of length
w,l - the sides of a rectangle
7 : 2 ⇒ 7x : 2x
Perimeter: P = 207cm
Perimeter: P = 2w + 2l
therefore: 2w + 2l = 207 |divide both sides by 2
w + l = 103.5 (cm)
w : l = 7 : 2 ⇒ w : l = 7x : 2x ⇒ w = 7x; l = 2x
subtitute
7x + 2x = 103.5
9x = 103.5 |divide both sides by 9
x = 11.5 (cm)
7x = 7 · 11.5cm = 80.5cm
2x = 2 · 11.5cm = 23cm
w = 80.5cm; l = 23cm
Area = wl
Area: A = 80.5cm · 23cm = 1851.5cm²
