If the perimeter is 28 units, then you know you will have to add the same four numbers to get the perimeter. What times 4 can get you to 28? 7. 7 x 4=28. So what plus 3 gets us to 7? 4. The answer is 4, or x=4.
First we must change these numbers to improper fractions:


So then we set it up:
÷ 
When we divide fractions like this, we must flip the second fraction and change the sign from division to multiplication like so:

Then we solve:

Then if we divide the numerator and the denominator by 9, we get:
or, in mixed-number form,
.
Answer:
y-intercept: 10
concavity: function opens up
min/max: min
Step-by-step explanation:
1.) The definition of a y-intercept is what the resulting value of a function is when x is equal to 0.
Therefore, if the function's equation is given, to find y-intercept simply plug in 0 for the x-values:

y intercept ( f(0) )= 10
2.) In order to find concavity (whether a function opens up or down) of a quadratic function, you can simply find the sign associated with the x^2 value. Since 2x^2 is positive, the concavity is positive. This is basically possible, since it is identifying any reflections affecting the y-values / horizontal reflections.
3.) In order to find whether a quadratic function has a maximum or minimum, you can use the concavity of the function. The idea is that if the function opens downwards, the vertex would be at the very top, resulting in a maximum. If a function was open upwards, the vertex would be at the very bottom, meaning there is a minimum. Like the concavity, if the value associated with x^2 is positive, there is a minimum. If it is negative, there is a maximum. Since 2x^2 is positive, the function has a minimum.
Answer:
5 : 12
Step-by-step explanation:
Cheerleaders : football players
20 : 48
5 : 12