Jamal is making two paintings using canvases that are similar rectangles. The length of the smaller canvas is 3 ft and the width is 5 ft.

What is the length of the larger canvas if the width is 10 ft?


Sagot :

Let's start with what we know:

Smaller canvas:
Length ([tex] L_{1} [/tex]) = 3ft
Width ([tex] W_{1} [/tex]) = 5ft

Larger canvas:
Length ([tex] L_{2} [/tex]) = ?
Width ([tex]W_{2} [/tex]) = 10ft

Since these are similar rectangles, we can cross-multiply to calculate the missing length. Here's that formula:

[tex] \frac{ L_{1} }{ L_{2} } = \frac{ W_{1} }{ W_{2} } [/tex]
So let's plug it all in from above:

[tex] \frac{ 3 }{ L_{2} } = \frac{ 5 }{ 10 } [/tex]
Now we cross multiply by multiplying the top-left by the bottom-right and vice versa:

[tex](3)(10) = (5)(L_{2})[/tex]
[tex]30 = 5L_{2}[/tex]
Now divide each side by 5 to isolate [tex]L_{2}[/tex]

[tex] \frac{30}{5} = \frac{ 5L_{2}}{5}[/tex]
The 5s on the right cancel out, leaving us with:

[tex]6 = L_{2} [/tex]

So the length of the larger canvas is 6 ft

It's not as complicated as you think. The smaller rectangle is 3ft with a width of 5ft. It's asking what the length of the larger canvas is if the width is 10ft. So you pretty much just do 10/5 which is 2 then you multiply 3ft by 2 and you get 6ft.

If you need any help just ask :)

-John