Answer:
P = (21.4a+36.6) cm
Step-by-step explanation:
Given that,
The width of a rectangle, b = (6.9a+8.5) cm
The length of a rectangle, l = (3.8a+9.8) cm
We need to find the perimeter of the rectangle. Perimeter is the sum of all sides. So,
P = 2(l+b)
Put all the values,
P = 2(6.9a+8.5+3.8a+9.8)
= 2(6.9a+3.8a+8.5+9.8)
= 2(10.7
a+18.3)
= (21.4a+36.6)
So, the perimeter of the rectangle is (21.4a+36.6) cm.
ANSWER
The restrictions are

EXPLANATION
We were given the rational function,

The function is defined for all values of a, except

This has become a quadratic trinomial, so we need to split the middle term.
We do that by multiplying the coefficient of
which is 5 by the constant term which is 3. This gives us 15.
The factors of 15 that adds up to 16 are 1 and 15.
We use these factors to split the middle term.

We now factor to get,

We factor further to get,

This implies that,

This gives

These are the restrictions.
Answer:
2 pencils
Step-by-step explanation:
3 - 1 = 2
Answer:
13 is the number.
Step-by-step explanation:
Given:
Twice the difference of a number and 9 equals 8.
Let the unknown number be 'x'.
Therefore, as per question:
The difference of 'x' and 9 = 
Twice the difference means 2 times the difference. So, we multiply 2 to the difference. Therefore,

Now, the above expression is equal to 8. So, we equate the above expression to 8. This gives,

Solving for 'x', we get:
Using distributive property of addition and distributing 2 inside the bracket. This gives,

Therefore, the unknown number is 13.
Now, we can verify our answer.

Therefore, the answer is correct.