Answer:
a) The correct option is C: 4x
b) The correct option is B: 2x
Step-by-step explanation:
a) Usually when we have a real number multiplying a variable, we do not need to write the multiplication symbol.
So instead of writing:
4×x
We can write:
4x
And this will be equivalent.
Then in this case the correct option is C.
b) We know that if we have the multiplication of A by n, this will be equivalent to add A n times.
Then if we have the sum of A, for example, 4 times, we have:
A + A + A + A
And this can be written as 4*A
In this case, we have the expression x + x.
So we are adding x two times, then this can be written as: 2*x, or, as we said earlier, this also can be written as 2x.
Then the correct option is option B.
I can help you but what is the operation of math
Answer:
0.3
Step-by-step explanation:
30/(30+20+50) = 30/100 = 0.3
Answer:
- Walnuts cost $1.75, chocolate chips cost $2.75
Step-by-step explanation:
<h3>Let the costs be:</h3>
- Walnuts - x
- Chocolate chips - y
<h3>Set equations as per question</h3>
For 7 pounds of walnuts and 9 pounds of chocolate chips, the total cost is $37:
For 5 pounds of walnuts and 3 pounds of chocolate chips, the total cost is $17:
<h3>Solve the system by elimination</h3>
Multiply the second equation by 3 and subtract the first equation, solve for x:
- 3(5x + 3y) - (7x + 9y) = 3(17) - 37
- 15x + 9y - 7x - 9y = 51 - 37
- 8x = 14
- x = 14/8
- x = 1.75
Find the value of y:
- 7*1.75 + 9y = 37
- 12.25 + 9y = 37
- 9y = 37 - 12.25
- 9y = 24.75
- y = 24.75/9
- y = 2.75
