Daniel rides his bicycle 21km west and then 18km north. how far is he from his starting point?

This is a right triangle. To find the length of the hypotenuse a^2 + b^2 = c^2.

21^2 + 18^2 = c^2

441 + 324 = c^2

765 = c^2

27.66 km

x=30

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