Answer:
Part 1) [tex]y=528[/tex]
Part 2) [tex]y=\frac{3}{4}x+4[/tex]
Part 3) Not a direct variation
Step-by-step explanation:
Part 1) we know that
A relationship between two variables, x, and y, represent a direct variation if it can be expressed in the form [tex]y/x=k[/tex] or [tex]y=kx[/tex]
In this problem we have
[tex]y=48, x=16[/tex]
Find the constant of proportionality k
[tex]y/x=k[/tex]
substitute the values
[tex]48/16=k[/tex]
[tex]k=3[/tex]
The equation of the direct variation is equal to
[tex]y=3x[/tex]
so
For [tex]x=176[/tex]
[tex]y=3(176)=528[/tex]
Part 2) we know that
the equation of the line in slope-intercept form is equal to
[tex]y=mx+b[/tex]
where
m is the slope
b is the y-coordinate of the y-intercept
we have
[tex]m=\frac{3}{4}[/tex]
Point [tex](-4,1)[/tex]
substitute the values in the equation and solve for b
[tex]1=\frac{3}{4}(-4)+b[/tex]
[tex]1=-3+b[/tex]
[tex]b=4[/tex]
the equation is equal to
[tex]y=\frac{3}{4}x+4[/tex]
Part 3) Tell whether the equation [tex]4x + y = 3[/tex] represents a direct variation
we know that
A relationship between two variables, x, and y, represent a direct variation if it can be expressed in the form [tex]y/x=k[/tex] or [tex]y=kx[/tex]
In the direct variation the constant of proportionality k is equal to the slope of the line and the line passes through the origin
In the linear equation [tex]4x + y = 3[/tex] the line does not passes through the origin
so
Not a direct variation