Answer:
x = 3 , X = -3
In x 2 = 9 , you need to get rid of the power of 2 in order to isolate just x This involves finding the square root. √ x 2 = x However there are 2 possible answers to a square root, a positive or a negative answer. x = ± √ 9 x = ± 3
Start with with original price and find 30% of that price:
30% of 810: (0.30)(810) = 243
Now take that 30% away:
810 - 243 = 567
That's the sale price: $567
Find 30% of the sale price:
30% of 567: (0.30)(567) = 170.10
Now add that 30% on to the sale price:
567 + 1701.0 = 737.10
The final price described is $737.10.
Now we need to relate that final price to the original price:
737.10 ÷ 810 = 0.91
This means that the final price is 91% of the original price.
Answer:
6:07
Step-by-step explanation:
8:22 minus 2 hours is 6:22, 1/4 an hour is 15 minutes so 22 minus 15 is 7, leading to the answer of 6:07 being your start time.
The surface area is 870 cm².
Since the base is a regular quadrilateral, each side is the same; dividing the perimeter by 4 will give us the side length:
60/4 = 15
To find the area, we square the side length:
15² = 225
There are two bases, so the area of these is 2(225) = 450
There are 4 lateral faces, so the lateral area is 4(105) = 420
Together, this gives us a total surface area of 870.
Answer:
Step-by-step explanation:
It appears to be the last step there that has evaded you. In the second line of work, you can see that what's in each set of parenthesis is exactly the same. Because of this, it is common and can be factored out. What's left is the 4x and the +5:
(5x - 3)(4x + 5)
That's factoring by grouping. It only works with polynomials that have an even number of terms so you can group them together in 2's.