7 x 18 = 7 x (10 + _ ) =(7 x 10 ) + (7 x _ )

= 70 + _

= _ square units

( " _ " means it needs to be answered )
( BTW this is 3rd-grade math )​

7

10

70

140

this is so easy

it has changed from the width and the height.

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