Can you retype this? It's kind of hard to understand what you are saying
I’m not sure what the first one is, but number 4 is A) y=2x+4
Answer:
x cubed minus y cubed is equal to 504
Step-by-step explanation:
First we need to know what the values of x and y are. We can do this pretty easily, by just solving both equations for x, and equating them to each other:
With the first:
x + y = 10
x = 10 - y
And with the other
x - y = 6
x = 6 + y
Now that we have two definitions of x, we can say that the expressions are equal, and solve for y:
10 - y = 6 + y
10 - 6 = y + y
4 = 2y
y = 2
And now that we know what y is, we can find x:
x = 10 - y
x = 10 - 2
x = 8
So x is equal to eight. We can check our answer by plugging x into the other equation and seeing if we get the same value for y:
x - y = 6
8 - y = 6
-y = 6 - 8
-y = -2
y = 2
So we know we solved that correctly.
Now if we cube each number, eight cubed is equal to 512, and 2 cubed is equal to 8. If we subtract the latter from the former we get 504.
so x cubed minus y cubed is equal to 504
Answer:
Step-by-step explanation:
You are to assume in both problems that the two triangles are similar. That is a very dangerous assumption -- especially in later math classes. But in this case, there is no other way to do the problem. The two sets of triangles look like they are proportional. So set up two ratios that are = to each other
On the left
long side small triange / long side large triangle = base small triangle / base large triangle
On the right
hypotenuse/longest leg = hypotenuse / longest leg.
Problem A
Set up the similar Proportion
5/40 = x/20 Cross Multiply
40x = 20*5
40x = 100 Divide by 40
x = 100/40
x = 2.5
Problem B
Again set up the similar triangle proportion
15/10 = x/2 Multiply by 2
15*2/10 = x
3 = x
