9514 1404 393
Explanation:
From your knowledge of the world, you know that ...
- the cost of multiple items is the sum of their individual costs
- multiplication can be used for repeated addition
- utility fees are the sum of fixed fees and usage-related fees
- for a phone plan, text message costs are a usage-related fee
The problem statement asks for the cost of a single text message. For the purpose of finding that value, it is convenient to represent it using the variable <em>t</em>. The problem statement says Eric was billed for 450 text messages, so we expect his usage-related fee to be 450t, the sum of the costs of 450 messages--using multiplication for the repeated sum.
The problem statement says Eric was billed 12.50 for fixed fees. So, we expect Eric's total bill to be ...
fixed fees + usage-related fees = 12.50 + 450t
The problem statement says Eric's total bill was 35.00, so we assume that is the sum of the above-listed fees. That is, the two ways to express Eric's total bill are equal.
12.50 +450t = 35.00
X + y = 15
xy = -312
x + y = 15
x - x + y = -x + 15
y = -x + 15
xy = -312
x(-x + 15) = -312
x(-x) + x(15) = -312
-x² + 15x = -312
-x² + 15x + 312 = 0
-1(x²) - 1(-15x) - 1(312) = 0
-1(x² - 15x + 312) = 0
-1 -1
x² - 15x + 312 = 0
x = -(-15) ± √((-15)² - 4(1)(312))
2(1)
x = 15 ± √(225 - 1248)
2
x = 15 ± √(-1023)
2
x = 15 ± 31.984i
2
x = 7.5 ± 15.992
x = 7.5 + 15.992 or x = 7.5 - 15.992
x = 23.492 or x = -8.492
x + y = 15
23.492 + y = 15
- 23.492 - 23.492
y = -8.492
(x, y) = (23.492, -8.492)
or
x + y = 15
-8.492 + y = 15
+ 8.492 + 8.492
y = 23.492
(x, y) = (-8.492, 23.492)
The two numbers that add up to 15 and mutliply to -312 are -8.492 and 23.492.
Answer:
Step-by-step explanation:
Answer:
What I'd do is pick one either decimal, percentage or fraction and convert the rest into that
Answer:
36.1 in.
Step-by-step explanation:
1:19 , 1.9in.
1.9 * 19
which equals 36.1 in.
(HOpe This hElps:)
If correct plz give brainliest ; )
