Y varies directly as x when x= 3 and y =12 find y when x =12

1 answer:

3 0

$\bf \qquad \qquad \textit{direct proportional variation}\\\\
\textit{\underline{y} varies directly with \underline{x}}\qquad \qquad y=kx\impliedby 
\begin{array}{llll}
k=constant\ of\\
\qquad variation
\end{array}\\\\
-------------------------------\\\\
\textit{we know that }
\begin{cases}
x=3\\
y=12
\end{cases}\implies 12=k3\implies \cfrac{12}{3}=k\implies 4=k
\\\\\\
thus\qquad \boxed{y=4x}
\\\\\\
\textit{when x = 12, what is \underline{y}?}\qquad \qquad y=4(12)$

You might be interested in

Write a equation of a line through (4, 6) and (-10, 2)

Ludmilka [50]

Answer:

y=2/7x+34/7

Step-by-step explanation:

the slope of this line is 2/7.

y=2/7x+?

? is the y-intercept.

Looking at the line that we have graphed, we can see that it intersects at 34/7 y.

the equation for the line that goes through 4,6 and -10, 2 is

y=2/7x + 34/7

4 0

1 year ago

Plz help me on my homework

pishuonlain [190]

The answer to the problem is D

4 0

2 years ago

Read 2 more answers

38. What is the surface area of a conical grain storage tank that has a height of 62 meters and a diameter of 24 meters? Round t

svetoff [14.1K]

1. The surface area of a cone S is S= $\pi r^{2}+ \pi rl$ , where r is the radius of the base and l is the slant height.

2. The slant height l is found as follows:

$l^{2}= OC^{2}+ OB^{2}$
$l^{2}= 12^{2}+ 62^{2}=144+3844=3988$

$l= \sqrt{3988}=63.15$

3.

$A=\pi r^{2}+ \pi rl=3.14(12)^{2}+3.14*12*63.15
$
$= 452.16+2379.492 =2831.652 ( m^{2} )$

$= 452.16+2379.492 =2831.652 ( m^{2} )$

4. The answer is C