How would I at least start out those two problems?
It looks to me like you already did. Now just follow through with it.
If the length of each side of the frame's inner dimension (i.e. the glass) is x, and the length of each side of the frame's outer dimension is x^2 - 3, then the area of the frame is:
A = (outer dimension)^2 - (inner dimension)^2
27 = (x^2 - 3)^2 - (x)^2
27 = x^4 - 6x^2 + 9 - x^2
27 = x^4 - 7x^2 + 9 <----- This is where you got to already.
0 = x^4 - 7x^2 - 18
0 = (x^2 - 9)(x^2 + 2)
Therefore, either x^2 = 9 or x^2 = -2... and you know it can't be the latter.
Thus, x^2 = 9 and therefore x = 3. The glass is 3" on each side.
<span>Each (outer) side of the frame is x^2 - 3 = 9 - 3 = 6" </span>
Answer:

Step-by-step explanation:
Remember that the sides of a cube always have the same length.
In this case the length of the sides L is:
.
The cubes have 6 faces. Then the surface area of the cube is equal to the area of its 6 faces.
Since all sides of the cube have the same measure, then the area of each face is:

Then the area of the 6 faces is:



Answer:
3m -5
Step-by-step explanation:
3(m - 3) + 4
Distribute
3m -9 +4
Combine like terms
3m -5
Answer:
I believe it's 1/4
Step-by-step explanation:
Answer:
3
Step-by-step explanation:
6^2=5^2+b^2
36=25+b
36-25=b
B= square root of 9
B= 3