John bought 24 pens and pencils. there were 6 more pens than pencils. how many pens were bought by john? plz show work

number of pens bought by John = 15

Step-by-step explanation:

John bought 24 pens and pencils. There were 6 more pens than pencils.

LEt x be the number of pens

and y be the number of pencils

John bought 24 pens and pencils. so x+y = 24 (equation 1)

There were 6 more pens than pencils.

pens= 6 more than pencils

x= y+6  (equation 2)

Now we solve for x  and y

Substitute equaton 2 in equation 1

x+ y =24

y+6+y = 24

2y+6 = 24

subtract 6 from both sides

2y = 18 ( divide by 2)

y=9

x= y+ 6 (plug in y =9)

x= 9+6 = 15

So number of pens bought by John = 15

22

step-by-step explanation:

answer: 204

step-by-step explanation:

we are told that the revenue is

x⋅(4080−10x)=−10x^2+4080x

this is a quadratic function, so to maximize it we should find the x-value of its vertex. recall that the x-value of the vertex of the parabola ax^2+bx+c is given by the formula −b/2a.

so in this case, we have a=−10 and b=4080, so the x-value of the vertex is

−b/2a= −(4080)/2(−10)=204