12 pens and 5 rulers cost $70 while 3 pens and 25 rulers cost $65.Find the price of each pen and ruler. Let x and y be the price of the pen and ruler respectively.
Use the fact that 12 pens and 5 rulers cost $70 to set up Equation 1.
Write the equation in the form ax + by = C, where a is positive.

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4

c.

step-by-step explanation:

substitution for (0,1)

y=x^2+4x+1

1=0^2+4(x)0+1

1=0+4(x)0+1

1=4(x)0+1

1=0+1

1=1

substitution for (-3,-2)

y=x+1

-2=-3+1

-2=-2

the answer is c

step-by-step explanation: i took a test with this question on it

it's a proportional graph.

step-by-step explanation:

8 x 5 = 40         (and you have -8x and -5y)

x= absiss

y= orderly

so you have a proportional graph.