Answer:
7/2 =x
Step-by-step explanation:
The triangles are similar so we can write a ratio to solve
2 4
---- = -------
x 7
Using cross products
2*7 = 4x
14 = 4x
14/4 = 4x/4
7/2 =x
Answer:
80000 square meters
Step-by-step explanation:
perimeter + dividing fence = 800
let a = length
let b = width
let c = length of dividing fence
perimeter = 2*a + 2*b
let's say...
c is the same as the length
2a + 2b + c = 800
2a + 2b + a = 800
3a + 2b = 800
area = length*width
area = a*b
area / b = a
3*(area/b) + 2b = 800
3*(area/b) = 800 - 2b
area/b = (800 - 2b)
area = (800 - 2b)*b
To make the area large, we make the right hand side large.
800b - 2b^2
If you put in terms of x, y it looks like a downward opening parabola, so the max area is at the vertex. Half way between the roots.
y = -2x^2 + 800x
y = -x^2 + 400x
0 = x*(-x + 400)
roots are x= 0 and x = 400
vertex is at x, aka b = 200
area at b=200 is (800 - 400)*200 = 80000
and a is area/b... 80000/400 = 200
Answer:
Step-by-step explanation:
m=1, (10,5)
y=mx+b
5=1(10)+b
5=10+b
b=-5
y=x-5
Let's go ahead and construct an equation to show this. Together, they have 50 goldfish. This can be represented as =50.
Since we don't know how many Todd has, we're going to make a variable. We'll name it T, for Todd.
What about Andres? How many does he have? 10 more than Todd. Well, if Todd's amount is T, and Andres has 10 more, we can express that as T+10.
Now, just put the two pieces together! T+10=50.
The next step is inverse operations. You want to find out how many T is, so you need to get rid of the 10. To take 10 away from something is doing what? Subtraction! Be warned, though; whatever you do to one side of the problem, you have to do to the other. 10-10 is 0, and 50-10 is 40. Since we took the 10 away and 50 is now 40, what you're left with is T=40.
Wait a second.. wasn't "T" Todd's amount? Yep! That means that Todd has 40 goldfish. And we already know that Andres has 10, so there's your answer!
Answer: D. n + q = 20
5n + 25q = 300
Step-by-step explanation:
Let n represent the number of nickels that you have.
Let q represent the number of quarters that you have.
Suppose you have 20 coins. It means that
n + q = 20
The total value of the coins is $3. The value of a quarter is $0.25 and the value if a nickel is $0.05. Therefore, the equation would be
0.05n + 0.25q = 3
Multiplying both sides of the equation by 100, it becomes
5n + 25q = 300
The correct option is
D. n + q = 20
5n + 25q = 300