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>
Right side:
(1/27)^(2x+10)
=(3^-3)^(2x+10)
= 3^(-6x - 30)
Re-write both sides:
3^(4x-5) = 3^(-6x - 30)
from here, you can solve x
4x - 5 = -6x - 30
4x + 6x = -30 + 5
10x = -25
x = -2.5
Your answer is 2’3’3!! (2*3*3 = 18)
hopefully this helps, good luck bud! :)
Answer is in the photo. I can only upload it to a file hosting service. link below!
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Answer:
sales tax is 1.5
Step-by-step explanation: