y = cx
when x = 8, y = 12
so that 12 = 8c which gives c = 12/8 = 1.5
50
2
If y and x are related inversely, then the equation for y can be said to be:y = k/xTo find the constant k, substitute 12 for y and 6 for x (a pair of values that are known to satisfy the equation).y = k/x12 = k/612 X 6 = k72 = kThe value of the variation constant k is 72.
x = 24
x2y = k (constant) so 36 x 2 ie 72 is the constant. If x = 3 then y = 72/9 = 8
a varies directly as b and a = 12 when b = 4. What is the constant of variation?
50
What is y? Fx varies with x, but y could be anything.
y = kx: 10 = 37k so k = 10/37 and y = 10x/37
pi
If y varies directly as x then k = 2.
If P varies directly with the square of Q then the equation would be in the form of P = kQ2, where k is the constant of variation so the new equation would be: P = 6Q2, so when Q = 12 we have P=6*122, or P = 864
Direct variation refers to two variable quantities have a constant (unchanged) ratio, in which a variable "varies directly with the other."In order to have a direct variation, the constant of variation must be not equal to 0 in the equation y=kx, where k is the constant.When you try to put 2x+3y=0 into that formula (y= form), you get:2x+3y=03y=-2x ;Subtract the 2xy=(-2/3)x ;Divide by 3Your constant of variation is -2/3, and since it is less than 0, it is does variate directly. Therefore, y varies directly as x.
Y=kx+m Y=-5x+m K=-5
Find an equation of variation where y varies directly as x. One pair of values is y = 80 when x = 40
Both are variations of certain kinds of equations. X=kY is a direct variation since X varies directly as Y and k is the constant of variation. X=k/Y is an inverse variation where X varies inversly as Y and k is the constant of variation. Both of these variations are also functions.
y=3x is a direct variation in that y varies directly with x by a factor of 3. Any linear equation (a polynomial of degree 1, which is a polynomial equation with a highest exponent of 1), is a direct variation of y to x by some constant, and this constant is simply the coefficient of the "x" term. Other examples: y=(1/2)x is a direct variation, and the constant of variation is 1/2 y=-9x is a direct variation, and the constant of variation is -9