Solutions
⇒15 Cookie to 40 brownies can be written as 15:40
⇒15:40 is the ratio we have to simplify
The GCF of 15 and 40 is 5 so we divide them by 5
15 ÷ 5 = 3
40 ÷ 5 = 8
3:8 is in simplest form
7% Of 9000 is 630. Then subtract 630 from 9000. So your answer becomes 8370.
Answer:
No solutions.
General Formulas and Concepts:
<u>Pre-Algebra</u>
- Order of Operations: BPEMDAS
- Equality Properties
<u>Algebra I</u>
- Solving systems of equations using substitution/elimination
- Solving systems of equations by graphing
- Expanding
- Finding roots of a quadratic
- Standard Form: ax² + bx + c = 0
- Quadratic Formula:

Step-by-step explanation:
<u>Step 1: Define systems</u>
2x - y = 9
4x² + 3y² - 2x + y = 16
<u>Step 2: Rewrite systems</u>
2x - y = 9
- Subtract 2x on both sides: -y = 9 - 2x
- Divide -1 on both sides: y = 2x - 9
<u>Step 3: Redefine systems</u>
y = 2x - 9
4x² + 3y² - 2x + y = 16
<u>Step 4: Solve for </u><em><u>x</u></em>
<em>Substitution</em>
- Substitute in <em>y</em>: 4x² + 3(2x - 9)² - 2x + (2x - 9) = 16
- Expand: 4x² + 3(4x² - 36x + 81) - 2x + (2x - 9) = 16
- Distribute 3: 4x² + 12x² - 108x + 243 - 2x + 2x - 9 = 16
- Combine like terms: 16x² - 108x + 234 = 16
- Factor GCF: 2(8x² - 54x + 117) = 16
- Divide 2 on both sides: 8x² - 54x + 117 = 8
- Subtract 8 on both sides: 8x² - 54x + 109 = 0
- Define variables: a = 8, b = -54, c = 109
- Resubstitute:

- Exponents:

- Multiply:

- Subtract:

Here we see that we start to delve into imaginary roots. Since on a real number plane, we do not have imaginary roots, there would be no solution to the systems of equations.
<u>Step 5: Graph systems</u>
<em>We can verify our results.</em>
<h3>Answer</h3>
Page No 7.13:
Question 1:
Add the following:
(i) 3x and 7x
(ii) −5xy and 9xy
ANSWER:
We have
(i) 3x + 7x = (3 + 7)x = 10x
(ii) -5xy + 9xy = ( -5 + 9)xy = 4xy