Let x = # of 25-cent stamps
y = # of 2-cent stamps
{ x+ y = 88
{ 0.25x + 0.02y = 15.56
60 25-cent stamps 28 2-cent stamps
I am going to explain this using the substitution method, considering it appears to be the best in this situation.
We know (from the bottom equation) that y can equal 3x+20. Using this knowledge, we substitute the y in the top equation for 3x+20. Now, we have an equation that looks like this:
3x+20=x^2+2x
Now we need to move x to one side and then do some radicals (square roots).
Subtract the 2x on the right (since it is smaller, negatives = NONONO), which will give you
x+20=x^2
Now, we take the square root of both sides to get
rad(x+20)=x
Now we have to simplify. 20 doesn't have a square root, but 4 goes into 20, and 4 has a square root of 2. This now becomes
2rad(x+5)
This doesn't simplify any further... we have a problem... no way to isolate x as far as my knowledge goes... Sorry, can't help you any further than that, but another person or your teacher might be able to. R.I.P...
For part A, The answer is that the car gets better gas mileage. We can see it from the graph that the number of gallons used is on the X axis, and the distance traveled using those number of gallons is on the Y axis. The easiest way to compare would be to look at the 1 gallon of gas. You can see that you can travel 25 miles on 1 gallon of gas. The truck on the other hand will get you 18 miles per gallon. Imagine putting 1 in for X, the Y value would be 18 if you did this. The graph just shows us a visual way of saying the same thing. To determine how much farther the car with a girl on 8 gallons of gas, you would just multiply 8 by 25 for the number of miles traveled by the car. You would multiply 8 by 18 to find the number of miles traveled for the truck. The answers are 200 miles for the car and 144 miles for the truck. 200-144=56 miles farther for the car.
Answer:
x = 35 , y = 72.5
Step-by-step explanation:
(a)
x and 35° are vertical angles and are congruent, then
x = 35
(b)
y. y and 35 lie on a straight line and sum to 180°, that is
y + y + 35 = 180
2y + 35 = 180 ( subtract 35 from both sides )
2y = 145 ( divide both sides by 2 )
y = 72.5
<h3>Therefore, correct option is C. option.</h3><h3>C. x=29/8c</h3>
