The formula of an area of a rectangle:
A = wl
We have l = w - 4 and A = 21.
Substitute:
w(w - 4) = 21 <em>use distributive property</em>
(w)(w) + (w)(-4) = 21
w² - 4w = 21 <em>subtract 21 from both sides</em>
w² - 4w - 21 = 0
w² - 7w + 3w - 21 = 0
w(w - 7) + 3(w - 7) = 0
(w - 7)(w + 3) = 0 ↔ w - 7 = 0 ∨ w + 3 = 0
w = 7 ∨ w = -3 < 0
l = w - 4 → l = 7 - 4 = 3
<h3>Answer: the length = 3 u.</h3>
17∠x-11 set up the equation like this
28∠x add 17 to the other side, and you get x is greater than 28
Answer:
A; infinitely many solutions
Step-by-step explanation:
first, let's simplify the first equation to make it simpler.
divide both sides by 5
y=3x-8
new system
y=3x-8
y=3x-8
as you can see, they are the same.
not mandatory but useful!⬇⬇⬇⬇
just to be more clear, let's substitute them. since they're both already in y=, we can make them both set to each other.
3x-8=3x-8
add 8 to both sides; subtract 3x from one side
0=0
the answer is A, Infinitely many solutions.
hope this helped <3333333
