Answer:
(a) 120 square units (underestimate)
(b) 248 square units
Step-by-step explanation:
<u>(a) left sum</u>
See the attachment for a diagram of the areas being summed (in orange). This is the sum of the first 4 table values for f(x), each multiplied by 2 (the width of the rectangle). Quite clearly, the curve is above the rectangle for the entire interval, so the rectangle area underestimates the area under the curve.
left sum = 2(1 + 5 + 17 + 37) = 2(60) = 120 . . . . square units
<u>(b) right sum</u>
The right sum is the sum of the last 4 table values for f(x), each multiplied by 2 (the width of the rectangle). This sum is ...
right sum = 2(5 +17 + 37 +65) = 2(124) = 248 . . . . square units
Answer: $10
Step-by-step explanation:
let x = the price of green fabric, then x+2 = blue fabric price
8x+5(x+2)=62
8x+5x+10=62
13x+10=62
13x=52
x=4
price of green fabric=$4
price of blue fabric=$6
4+6=$10
Answer:
12.5 inches? I think
Step-by-step explanation:
gotta go do my work
Answer:
B. x < -8 or x > 8
Step-by-step explanation:
You can use process of elimination to solve this problem by going through every solution and testing them out, but let's jump right to B.
Process:
You know that since the inequality states that x^2 has to be greater than 64, x has to be more than 8, or less than -8.
This is because 8^2 = 64, and -8^2 = 64, and the inequality requires the answer to be more than 64.
Looking at B., you can see that if x is < -8, the square of, for example, -9, would be 81. This is greater than 64, so this works!
Now, B. also has an alternative. The 'or' is a major clue to which is the correct answer, since the square root of any number can be positive or negative. (-8^2 = 8^2)
The 'or' states that x must be greater than 8. So, for example, if we take the square of 10, we get 100, and that is also greater than 64.
We've proven that this solution is accurate for both parts, so it is definitely the one we want!
Hope this helps!
