Answer:
Step-by-step explanation:So we know x + y = 21 and 5x +10y = 165 We line them up in columns x + y = 21 5x +10y = 165 To eliminate the x variable, I'll multiply every element in the 1st equation by -5. -5x + -5y = -105 5x + 10y = 165 Now we combine (add) the equations, which eliminates x altogether. 5y = 60 ... y = 12 From there, x + 12 = 21 ... x = 21-12 ... x = 9 You should double check. Do 9 nickles and 12 dimes equal $1.65? A very important thing to remember using this method is to do the same thing to each element in the equation that you change! I hope that helps.
/50 = /25•2
/25 • /2 further written as
5 • /2 simplified form
so A
It’s would be 24 photos per day
Answer:
School A
Step-by-step explanation:
School A has a ratio of 18/225 = 2/25 staff to students
School B has a ratio of 23/322 = 2/28 = 1/14 staff to students
Assuming that a better ratio means more staff per students School A has a better ratio
Answer:
200√3
Step-by-step explanation:
The triangle given here is a special right triangle, one with angles measuring 30-60-90 degrees. The rule for triangles like these are that the side opposite the 30° angle can be considered x, and the side opposite the 60° angle is x√3, while the hypotenuse, or side opposite the right angle, is 2x. All we need to know here are the two legs to find the area.
Since b is opposite the 30° angle, it is x, while side RS is opposite the 60° angle, meaning it is equal to x√3, meaning that the area of the triangle is 1/2*x*x√3. We can substitute in 20 for x, making our area 1/2*20*20√3. Multiplying we get 10*20√3, or 200√3.
