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!
Answer:When two lines intersect they form two pairs of opposite angles, A + C and B + D. Another word for opposite angles are vertical angles. Vertical angles are always congruent, which means that they are equal. Adjacent angles are angles that come out of the same vertex.
here you go
Answer:
The formula of area is Pi×R×R
and then you add all sides and answer of your question is 30cm
Let the two numbers be x and y.
According to your question;
x + y = 7
10y + x = 10x + y + 9
By equation 1 ; x = 7-y
Substituting the value of x ;
10y + ( 7 -y) = 10(7-y) + y + 9
9y + 7 = 70 -10y + y + 9
9y + 7 = 70 - 9y + 9
=> 18y = 70 -7 + 9
=> 18y = 72
=> y = 4
Substituting for x ;
x = 7 - y
=> x = 7 -4
=> x = 3
Thus, x = 3 and y = 4;
=> The number is 34.
Answer:
Step 3 is not correct (should be , not
Step-by-step explanation:
The expression that we have to simplify is:
We proceed step-by-step, in order to find the mistake did by Cedric:
1) First, we factorize the 5 outside:
--> this step is correct
2) We add +16 and -16 inside the brackets:
--> this step is correct
3) We rewrite the term as the square of a bynomial, which is , so the expression becomes
--> we notice that this step is wrong: in fact, Cedric wrote , which is not correct.
4) Now we continue: we rewrite -16+3 as -13,
5) Finally, we multiply the 5 by the terms in the bracket: