Ask question

Ask question

All categories

4 years ago

5

A number a decreased by 7 is 2.

2 answers:

umka21 [38]4 years ago

7 0

Answer:

9

Step-by-step explanation:

Let's first convert this to numbers. When a number is decreased by a certain amount, that is the same as saying that something is subtracted from it. Therefore:

a-7=2

Add 7 to both sides:

a-7+7=2+7

a=9

Hope this helps!

Minchanka [31]4 years ago

5 0

Answer:

9

Step-by-step explanation:

If a number (Let's call it x) has been subtracted by 7 (x - 7) then to find the previous number you just do the opposite. Let's call the end result y. 2 + 7 = x (Or y + 7 = x). <u>2 + 7 = 9.</u>

You might be interested in

A set of small building blocks contains 48 blocks. The blocks are cube-shaped and have an edge length of 1/2 inch. If all the bl

svlad2 [7]

Answer:

6 in^3

Step-by-step explanation:

Each block is a cube with edge length of 1/2 inch.

V = s^3

V = (1/2 inch)^3

V = 1/8 inch^3

Each cube has a volume of 1/8 cubic inch.

48 blocks have 48 times the volume of one block.

volume of prism = 48 * 1/8 in^3

volume of prism = 6 in^3

4 0

3 years ago

Use the limit definition of the derivative to find the instantaneous rate of change of

Lynna [10]

$f'(4) = 43$

Explanation:

Given: $f(x)=5x^2 + 3x + 3$

$\displaystyle f'(x)= \lim_{h \to 0} \dfrac{f(x+h) - f(x)}{h}$

Note that

$f(x+h) = 5(x+h)^2 + 3(x+h) + 3$

$\:\:\;\:\:\:\:= 5(x^2 + 2hx + h^2) + 3x + 3h +3$

$\:\:\;\:\:\:\:= 5x^2 + 10hx + 5h^2 + 3x + 3h +3$

Substituting the above equation into the expression for f'(x), we can then write f'(x) as

$\displaystyle f'(x) = \lim_{h \to 0} \dfrac{10hx + 3h + 5h^2}{h}$

$\displaystyle\:\:\;\:\:\:\:= \lim_{h \to 0} (10x +3 +5h)$

$\:\:\;\:\:\:\:= 10x + 3$

Therefore,

$f'(4) = 10(4) + 3 = 43$

8 0

3 years ago

6.2 x 4.3 + 7.6 simplify

____ [38]

6.2x4.3= 26.66; Add that to 7.6= 34.26; then simplify

4 0

3 years ago

Solve for a 7a + 2a + a − 9a = 20

Ira Lisetskai [31]

Answer:

a = 20

Step-by-step explanation:

7a + 2a + a − 9a = 20

Combine like terms

10a -9a = 20

a =20

7 0

3 years ago

An airport is studying the noise levels of jets during takeoff as they pass over a neighborhood. They find that at the present t

avanturin [10]

Answer: 2.28%

Step-by-step explanation:

Given: An airport find that at the present time, the mean noise level is 103 decibels and the standard deviation is 5.4 decibels.

The distribution of noise levels(x) for all jets during takeoff over the neighborhood has a normal distribution.

The probability that jets have a noise level less than 92.2 decibels when taking off over this neighborhood will be :-

$P(X$

Hence, the percent of these jets have a noise level less than 92.2 decibels when taking off over this neighborhood = 2.28%

6 0

3 years ago