Answer:
Work:
x^2 + 4x - 4 = 8
x^2 +4x -12 = 0
(x + 6) (x - 2) = 0
x = -6 and 2
Answer: first option
I hope this helps!
Step-by-step explanation:
did this on edge :)
hope this helps ~ xoxo ANGIEEE CRAZZZY :3
Answer:
29 square = 20 square+ b square
b= 21
The dimensions of the house should be 7 m by 13 m.
If the house is to be centered, we will take the same amount from the width as we do from the length of the lot for the dimensions. This gives us (10-x) and (16-x) as the dimensions.
The area of a rectangle is found by multiplying the length and width:
(10-x)(16-x) = 91
Multiplying the binomials we have:
10*16 - x*10 - x*16 -x*(-x) = 91
160 - 10x - 16x --x² = 91
160-10x-16x+x² =91
Combine like terms:
160-26x+x²=91
Rewrite this in standard form:
x²-26x+160=91
Subtract 91 from both sides:
x²-26x+160-91 = 91-91
x²-26x+69 = 0
Factoring this, we look for factors of 69 that sum to -26. -23*-3 = 69 and -23+-3 = -26, so:
(x-23)(x-3) = 0
Using the zero product property we know that either x-23=0 or x-3=0, so x=23 or x=3.
x was the amount we take off of the width and length of the lot; if we took 23m off of it, 10-23 gives us a negative amount, which is not realistic. This means both the width and length are subtracted by 3.
10-3 = 7 and 16-3 = 13.
These are the dimensions of the house.
Answer:
343 : 729
Step-by-step explanation:
A cube is made up of 6 square faces. If each face has a side length of a, we can find the surface area of that cube with the formula 
, since we'll have 6 faces with area a². Let's call the edge length of the first cube a and the edge length of the second cube b. The ratio between their surface areas is then 6a² : 6b², or simply a² : b². If we compare this to our given ratio 49 : 81, we can see that a² = 49 and b² = 81, or, square rooting both equations, a = 7 and b = 9.
The volume of a cube with a side length a is a³, so the ratio between our cubes here must be a³ : b³. Using the values for a and b we just found, this ratio becomes 7³ : 9³, which we can simplify to 343 : 729.
Evaluating will be = (w+2)(w+5)
Expanding will be = w^2+7w+10
And Factorizing will be = (w+2)(w+5).
