If we set both equations equal to each other, we have 7/x = 4/5, giving us the answer x = 8 3/4, or x = 8.75
When we say that y varies <em>directly </em>with x, we mean that whatever value x is scaled up by, y will be scaled up by, too. The simplest kind of direct variation is one where y = x for all values of x. If you multiply x by some value, y must be multiplied by that same value.
More generally, though, you'll have something of the form y = kx, where the variable k here is referred to as the <em /><em>constant of proportionality.</em> Another way you can think of k is as the <em>ratio of y to x</em>.
In this problem, you're given a set of values for x and y, and you'll need to use those to find the constant of proportionality before you set up an equation relating x to y. Substituting our general equation y = kx for the given values, we have:
-5 = k(15)
To get k, simply divide both sides by 15 to obtain:
k = -5/15 = -1/3
So, our general equation, for <em>any x</em>, would be y = (-1/3)x
s.a=C.A xH
v of n.o.2 =lxwxh
Step-by-step explanation:
v of no.3=πr2h and s.a=πdh
no.1=area of cross section x area of all faces and v=area of cross section x length
try those ones
Answer:
12
Step-by-step explanation:
Since they are parallel then
(7x - 8) + (11x - 28) = 180
18x - 36 = 180
18x = 216
x = 12
Answer:
Step-by-step explanation:
The variables are defined, so we only need to express the given relations. The total of the two quantities is 14.
x + y = 14
The sum of costs is $72. Totts are $8 each, so x of them will cost 8x. Elentines are $3 each, so y of them will cost 3y.
8x +3y = 72