Respuesta :
Answer:
D. 300
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
- Left to Right
Equality Properties
- Multiplication Property of Equality
- Division Property of Equality
- Addition Property of Equality
- Subtraction Property of Equality
Algebra I
- Solving systems of equations using substitution/elimination
Step-by-step explanation:
Step 1: Define Variables
Stuffed bears = b
Stuffed dogs = d
Step 2: Define Systems
$7b + $8d = $3800
b + d = 500
Step 3: Rewrite Systems
b + d = 500
- [Equality Property] Multiply everything by -7: -7b - 7d = -3500
Step 4: Redefine Systems
7b + 8d = 3800
-7b - 7d = -3500
Step 5: Solve for d
Elimination
- Combine 2 equations: d = 300
Step 6: Define Answer
d = 300 means that the students bought 300 stuffed dogs.
Answer:
D
Step-by-step explanation:
Remark
Let the stuffed bear = x
Let the stuffed dog = y
Equations
x + y = 500 (1)
7x + 8y = 3800 (2)
Solution
There are two ways you could do this. You can use substitution or you could use multiplying equation 1 by either 7 or 8 to get rid of the x or y.
Multiply (1) by 7
7x + 7y = 3500 (3) Write equation (2) below (3) and subtract
7x + 8y = 3800 Subtract
-y = - 300 Multiply by - 1
y = 300
Use the result for y to get x using equation 1
x + y = 500
x + 300 = 500 Subtract 300
x = 500 - 300
x = 200
Stuffed bears = 200
Stuffed dogs = 300