Answer:
1. n= 14
2. n=3
Step-by-step explanation:
For the first problem, let's break down the equation. The number being thought about can be represented by <em>n</em>. Then <em>n </em>is increased by 7, or simply put 7+ <em>n. </em>The sum is 21, so to find n you can use the equation 7 + n = 24 and solve for <em>n, </em>which is 14.
For problem two, the same strategy can be used. The number is <em>n, </em>multiplied by 9. So, 9 * <em>n</em> is equal to 27. Solve for n by isolating n, and the answer is 3.
Answer:
b. 6|x|
Step-by-step explanation:
√(36x²) = √36√(x²)= 6|x|
Because √ from the number can be only positive.
Answer:
Step-by-step explanation:
Show that if 3x – 7 = 5, then x = 4.
Here, our given statement is 3x – 7 = 5, and we're asked to prove x = 4.
x=4
Statements Reasons
1. 3x – 7 = 5 Given
2. 3x – 7 + 7 = 5 + 7 Addition of 7 to equation (1)
3. 3x + 0 = 5 + 7 Substitution of –7 + 7 = 0 into (2)
4. 3x = 5 + 7 Substitution of 3x + 0 = 3x into (3)
5. 3x = 12 Substitution of 5 + 7 = 12 into (4)
6. 3x⁄3 = 12⁄3 Dividing equation (5) by 3
7. x = 12⁄3 Substitution of 3x⁄3 = x into (6)
8. x = 4 Substitution of 12⁄3 = 4 into (7)
Is there such a thing as being too descriptive? Yep, and that was it, since over half the proof was devoted to telling the reader how to do arithmetic. We'll typically take numerical computation for granted, and write proofs like this:
answer: 22
15/7.5 = x/11
cross multiply
7.5x = 165
divide by 7.5 on both sides to get the x alone
7.5x/7.5 = 165/7.5
x = 22
the tree is 22 feet
sorry if it’s wrong