PLZ HELP HURRY !!!!!!

A radio is being discounted 20%. If the sale price is $51.44, what was the original price of the radio? A. $12.86, B. 64.30, C.

katrin2010 [14]

The equation for decreasing a price by 20% is
original price x 0.8 = sale price

Here, we can fill in the sale price so
original price x 0.8 = 51.44

This can be rearranged to show:
51.44 ÷ 0.8 = original price

So the original price was $64.30

Answer = B - $64.30

7 0

3 years ago

Read 2 more answers

In a circle a chord 10 inches long is parallel to a tangent and bisects the radius drawn to the point of tangency. How long is t

Lorico [155]

Check the picture below.

keeping in mind that the point of tangency for a radius line and a tangent is alway a right-angle, since the "red" chord is parallel to the "green" tangent line outside, then the chord is cutting the "green" radius there in two equal halves at a right-angle, as you see in the picture.

we know the chord is 10 units long, so 5 + 5, since is perpendicularity with the radius will also cut the chord in two equal halves.

anyhow, all that said, we end up with triangle you see on the right-hand-side, and then we can just use the pythagorean theorem.

$\bf \textit{using the pythagorean theorem}
\\\\
c^2=a^2+b^2
\qquad 
\begin{cases}
c=hypotenuse\\
a=adjacent\\
b=opposite\\
-------\\
c=2a\\
a=a\\
b=5
\end{cases}\implies (2a)^2=a^2+5^2$

$\bf (2^2a^2)=a^2+25\implies 4a^2=a^2+25\implies 3a^2=25
\\\\\\
a^2=\cfrac{25}{3}\implies a=\sqrt{\cfrac{25}{3}}\implies a=\cfrac{\sqrt{25}}{\sqrt{3}}\implies a=\cfrac{5}{\sqrt{3}}
\\\\\\
\textit{and then we can \underline{rationalize the denominator} }
\\\\\\
a=\cfrac{5}{\sqrt{3}}\cdot \cfrac{\sqrt{3}}{\sqrt{3}}\implies a=\cfrac{5\sqrt{3}}{\sqrt{3^2}}\implies a=\cfrac{5\sqrt{3}}{3}$

7 0

3 years ago

How many real number solutions are there to the equation 0=-3x^2 + x -4

natta225 [31]

We have that
the equation
y=-3x² + x -4
the real number solutions are the points x intercept of the graph
are the points when y=0

using a graph tool
see the attached figure

the graph has no point of intersection with the x axis
therefore

the answer is
there are zero real numbers solutions