I am going to do the first 2 problems and show my work that way you know how to do it yourself.
So first of all, the foil method:
(a+b) (c+d) = ac+ad+bc+bd
1. (3xy-1) (4xy+2) = (3xy*4xy) + (3xy*2) + (-1*4xy) + (-1*2)
(3xy-1) (4xy+2) = (12x^2y^2) + (6xy) + (-4xy) + (-2)
(3xy-1) (4xy+2) = (12x^2y^2) + (6xy-4xy) - 2
(3xy-1) (4xy+2) = 12x^2y^2 + 2xy - 2
2. <span>(2x-3y) (4x-y) = (2x*4x) + (2x*-y) + (-3y*4x) + (-3y*-y)
(2x-3y) (4x-y) = (8x^2) + (-2xy) + (-12xy) + (3y^2)
</span> (2x-3y) (4x-y) = 8x^2 + (-2xy-12xy) + 3y^2
(2x-3y) (4x-y) = 8x^2 - 14xy + 3y^2
I hope this helps!
Each side of a box is s = 2.5 units
volume of one box is length * breadth * height
since its a cube all sides are equal
volume of one box = s³ = 2.5³
since there are 4 boxes,
total volume V = 4s³
V = 4 * 2.5³ = 4 * 15.625
= 62.50 cubic units
third response is correct
Answer:
2x + y = 12 & x = 9 - 2y --- (x = 5, y = 2)
x + 3y = 16 & 2x - y = 11 --- (x = 7, y = 3)
y = 11 - 2x & 4x - 3y = -13 --- (x = 2, y = 7)
2x + y = 11 & x - 2y = -7 --- (x = 3, y = 5)
Step-by-step explanation:
To find the volume it is Length x Width x Height
so 7 x 5 x 4 = 140cm
140 cm is the answer
Hoped this helped =)