x will represent the first unknow number
6x will represent the second number
the two numbers together will equal 21
6x + x = 21 combine like terms
7x =21 divide both sides by 7
x =3
Hope that helps.
brainliest is always appreciated.
13 feet wide.
156/12=13
Brainliest plz
The amount of radioactive material that would remain by the 7th hour of decay is 0.12 grams.
<h3>
Exponential function</h3>
An exponential function is in the form:
y = abˣ
where y,x are variables, a is the initial value and b is the multiplicative factor.
Let y represent the amount of substance remaining after x hours. Hence:
a = 9375, at x = 4, y = 15:
15 = 9375(b)⁴
b = 0.2
y = 9375(0.2)ˣ
For the 7th hour, x = 7:
y = 9375(0.2)⁷ = 0.12
The amount of radioactive material that would remain by the 7th hour of decay is 0.12 grams.
Find out more on Exponential function at: brainly.com/question/12940982
Answer:
45
Step-by-step explanation:
1 yard= 3 feet
Answer:

Step-by-step explanation:
Given
Shape: Pentagon




Required
Find D
From the sum of angles in a Pentagon; we have that

Substitute values for A, B, C and E

Collect Like Terms


Collect Like Terms


<em>Hence, from the list of given options, the correct answer is 170</em>