Sounds like "formulas"! y = ax^2 + bx + c involves the variable x and the constants {a, b, c}. The "2" indicates "squaring function."
Answer:
1st one
Step-by-step explanation:
The answer to question 34:
Let 'x' = pounds of gravel. The ratio of mulch to gravel is given 2 1/4 | 1 1/3. Which equals 9/4 | 4/3 = 27/16.
So the total gravel and much is equal to x + 27/16x = 172
Solving for 'x'
43/16 x = 172
x = 172 (16/43) = 64 pounds of gravel Mulch = 27/16x = 64 (27/16)= 108 pounds
The answer to question 35:
A.) 1,080 beats per minute at rest and 1,500 beats per minute while running.
B.) 4,500 (while running) - 3,240 (at rest) = 1,260 more beats while running than at rest.
Based on the calculations, the unknown number is equal to 
- Let the unknown number be x.
<h3>How to find an
unknown number:</h3>
Translate the word problem into an algebraic expression, we have;
Adding 21 to the unknown number:

Multiplying the result by 3:

84 more than two-thirds of the unknown number:

Equating the equations, we have:

Cross-multiplying, we have:

Read more on word problems here: brainly.com/question/13170908
The systems of linear equations have been matched with their respective solutions as shown in the image attached below.
<h3>What is a system of linear equations?</h3>
A system of linear equations can be defined as an algebraic equation of the first order that has two (2) variables with each of its term having an exponent of one (1).
In this exercise, you're required to match the systems of linear equations with their respective solutions as shown in the image attached below.
Read more on linear equations here: brainly.com/question/2030026
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