Answer:
3
Step-by-step explanation:
(40/5)-7+2
PEMDAS says parentheses first, so divide inside the parentheses
(8)-7+2
Then add and subtract from left to right
1 +2
3
Answer:
Step-by-step explanation:
SV = RV
2x+2 = 10
x = 4
r² = RV² + VZ² = 10²+7.5² = 156.25
UZ = √[r²- (QR/2)²] = √[156.25 - 10²] = √56.25 = 7.5
The number of minutes for which Keith was billed = 97
Step-by-step explanation:
Step 1:
It is given that Keith pays a fixed fee of 3$ a month and 11 cents per minute for the number of minutes used.
Total cost = Fixed cost + Per minute cost
If x represents the number of minutes consumed in a month then we can compute the total cost using the below equation:
Total cost = 3$ + 0.11 * x
Step 2:
The total cost is 13.67$
Substituting in the equation we get
13.67 = 3 + 0.11 * x
x = 10.67 / 0.11 = 97 minutes
Step 3:
Answer:
The number of minutes for which Keith was billed = 97
She must have multiplied it by 5.
That would've given her:
x - y = 15
2.5x + y = 25
Now we can add them and the y-terms will eliminate each other. Because one is -y, and the other is positive y. -y + y = 0.
9514 1404 393
Answer:
x = 1 or 5
Step-by-step explanation:
The notion of "cross-multiplying" is the idea that the numerator on the left is multiplied by the denominator on the right, and the numerator on the right is multiplied by the denominator on the left. This looks like ...

Then the solution proceeds by eliminating parentheses, and solving the resulting quadratic equation.

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<em>Comment on "cross multiply"</em>
Like a lot of instructions in Algebra courses, the idea of "cross multiply" describes <em>what the result looks like</em>. It doesn't adequately describe how you get there. The <em>one and only rule</em> in solving Algebra problems is "<em>whatever is done to one side of the equation must also be done to the other side of the equation</em>." If you multiply one side by one thing and the other side by a different thing, you are violating this rule.
What looks like "cross multiply" is really "<em>multiply by the product of the denominators</em> and cancel like terms from numerator and denominator." Here's what that looks like with the intermediate steps added.
