1). A box is ( 2x -3 ) by ( x + 5 ) by ( 3x + 1 ), what is the volume of the box if x = 3 cm?
2). The formula for the area of a triangle is A= bh/2 if the base (b) = 10 cm and the height (h) = 6 cm, what is the area of the triangle?
3). The length (l) of the rectangle is x² + 2x - 3 and the width (w) is 5x + 4, what is the perimeter of the rectangle?
4). From the sum of 3x³ + 7x² - 5 and 2x² + 3x + 8 take away 5x² + x - 5.
5). What should be added to 3x³ + 4x² - 7 to have a sum of 4x³ + x² + 5
answer
1.substitute 3cm to all x
(2(3)-3)x(3+5)x(3(3)+1)
[tex]\huge\red{\boxed{1. \: =3x8x10= 240}}[/tex]
[tex]\red{\boxed{2. \: 10x6=60÷2=30cm²}}[/tex]
[tex]\red{\boxed{3. \: x²+2x-2 + 5x+4 = x²+7x+1}}[/tex]
[tex]\huge\red{\boxed{4. \: 3x³+4x²+2x+8}}[/tex]
[tex]\huge\red{\boxed{5. \: x³-3x²+12}}[/tex]
