<h3>
Answer:</h3>
- -100x +100; 3
- 5x +81; 162
<h3>
Step-by-step explanation:</h3>
The distributive property is your friend. It tells you ...
a(b + c) = ab + ac
It can also be used to simplify the product of binomials (or other polynomials).
(a +b)^2 = (a +b)(a +b) = a(a +b) + b(a +b) = a^2 +ab +ab +b^2
(a +b)^2 = a^2 +2ab + b^2 . . . . . . . worth remembering
1. (x -10)^2 -x(x +80) = (x^2 -20x +100) +(-x^2 -80x)
= -100x +100 . . . . . . simplified form
For the purposes of calculation, it can be easier to factor out 100:
= 100 (1 -x)
Then for x = 0.97
= 100(1 -0.97) = 100(0.03) = 3
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2. (2x +9)^2 -x(4x +31) = (4x^2 +36x +81) -4x^2 -31x = 5x +81
For x = 16.2, this is ...
5(16.2) +81 = 81 +81 = 162
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The purpose of the attachment is to show the evaluation is correct.
Answer:
255
Step-by-step explanation:
total cost paid = fixed cost + total variable cost
total variable cost = distance travelled x variable cost per unit
two equations can be derived from the question
a + 10b = 105 equation 1
a + 15b = 155 equation 2
a = fixed cost
b = variable cost per unit
Subtract equation 1 from 2
5b = 50
b = 10
Substitute for b in equation 1
a + 10(10) = 105
a = 105 - 100 = 5
a = 5
cost of travelling a distance of 25km
5 + 10(25) = 255
5 Erasers, 4:1 is equal to 20:5, if you just multiply both numbers by 5
Question 1:
If 18 earmuffs fit on one shelf then divide 567 by 18 which is 31.5
Question 2:
Do the same thing for this one, divide 327 by 12 and you get $27.25
She is not in credit overload because her total is $2240 so she has an extra 15 dollars left from her salary
