# Tutor profile: Alec C.

## Questions

### Subject: Geometry

Find the Surface area on a cylinder that is 10m high and has a radius of 3m.

Surface area: remember that finding the surface area means that we are finding the area around the shape. When finding a surface area of a shape I like to just think of it as finding the areas of all the 2D shapes that make the 3D shape. So for a cylinder we have two circles and one rectangle. Area of the circles: (remember the formula for a circle is 2πr^2=Area) 2π(3m)^2=18π m^2 is the area of one circle. Area of the rectangle: (remember the formula for a rectangle is b*h=Area) b=2πr (Because the base of the rectangle is connected to a circle) h=10m So, b*h=2π3m*10m= 60π m^2 is the area of the rectangle Final Area: now we bring it all together 60π m+2*18π m=96π m^2 96π m^2 is the surface area of the cylinder.

### Subject: Calculus

Given y=x(x^2+3) find y'=

Given y=x(x^2+3) y=x(x^2+3) (simplify before taking the derivative) y=x^3+3x (take derivative) (remember y=x^a y'=ax^a-1) y'=3x^2+3 (final answer

### Subject: Algebra

Solve for X: 1) X+4=7 2) X+4X=10 3) 4X+8Y=12

1) X+4=7 X+4=7 (put X on one side) X+4-4=7-4 (subtract 4 from each side) X+0=3 X=3 (Final Answer) 2) X+4X=10 X+4X=10 ( Combine X's) 5X=10 5X=10 ( Divide both sides by 5) (5/5)X=10/5 X=2 (Final Answer) 3) 4X+8Y=12 4X+8Y=12 (Get the 4X alone) 4X=12-8Y 4X=12-8Y (now divide both sides by 4) (4/4)X=(12/4)-(8/4)Y X=3-2Y (final answer)

## Contact tutor

needs and Alec will reply soon.