Answer:

Step-by-step explanation:
A rectangle is inscribed in a circle of radius r.
Radius of the circle is 'r' . the diameter of circle is 2 times radius is 2r
The diameter of the circle becomes the diagonal of the rectangle.
The one part of the rectangle forms a triangle with hypotenuse 2r
Triangle is a special 30:60:90 degree angle
the ratio of the special triangle is 
Hypotenuse is '2r' , so the ratio becomes

So the width of the rectangle is 'r' and length of the rectangle is 
Perimeter = 2 times length + 2 times width

We could find the error first, but if we solve the equation, we can compare our answers to find the error. So,
7x + 12 + 3x = 8
10x + 12 = 8
10x = -4
x = -4/10
x = -2/5.
When we compare the two, we see that our second line is vastly different, and we can easily isolate the mistake, finding that it occurs when they disregard the variable in the 3x term and subtract 8 by 3 rather than combining the terms 3x and 7x together.
Answer:
1:0.06
Step-by-step explanation:
since there is a 6% sales tax, which is the same as 0.06. to calculate your tax, you would multiply both of the sides of the ratio by 75, and the left side will show you subtotal of what you are buying, the right will show tax.
Option 1 : -22
using formula
(a + b )(a - b ) = a^2 - b^2
(√10 + 2√8) (√10 - 2√8)
= (√10)^2 - (2√8)^2
= 10 - 2×2×8=10-32
= -22
2nd question answer is option 3
Answer:
If you mean |x| and |-x| yes they are equal.
Step-by-step explanation:
Brackets do not exactly specify the meaning of absolute value.
On most keyboards, above the enter button on the main keyboard part (not the keypad one) there is a back slash symbol \ and if you hold shift, there might be another symbol | which more accurately represents absolute value,
If you aren't talking about the absolute value, then no.