2/5(x - 4) = 2x
2/5x - 8/5 = 2x....multiply everything by 5
2x - 8 = 10x
-8 = 10x - 2x
-8 = 8x
-8/8 = x
-1 = x <===
Answer:
Step-by-step explanation:
An Additive Verse is a pair of numbers whose sum is zero.
Example: the additive Inverse of -5 is +5
Therefore: the Additive Inverse of -10 1/4 would be +10 1/4
Let x denote the number of pages holding 2 cards and y
denote the number of pages holding 3 cards.
So his entire number of card would be represented by 2x + 3y, which is given as
18.
2x + 3y = 18
Subtract 3y from the two sides:
2x = 18 – 3y
then divide both sides by 2:
x = (18 – 3y)/2
We know that x must be an integer. So 18 – 3y must be a multiple of 2. Since 18
is a multiple of 2, 3y is also a multiple of 2. Then y must be a multiple of 2
too.
Let's start with y = 0.
When y = 0, x = (18 – 3(0))/2 = 9.
When y = 2, x = (18 – 3(2))/2 = 6.
When y = 4, x = (18 – 3(4))/2 = 3.
When y = 6, x = (18 – 3(6))/2 = 0.
Thus there are 4 ways to display his figures.
The equation would be 12x+85=y
x= # of people
y= Total amount of money
Edit: I did #4 sorry
Answer:
1.
a. 20 m²: barn door is 5m x 4m
b. 468 m²:surface area of barn
i. left and right barn walls: 2(15 x 7) = 210
ii. back wall: 7 x 8 = 56
iii. front wall: (7 x 8) - 20* = 36
*20 for the barn door
iv. front of roof: (4 x 4) / 2 = 8 x 2* = 16
*I split the triangle into 2 smaller triangles
v. sides of roof: 2(5 x 15) = 150
2.
a. 15 m²: silo door is 3m x 5m
b. 244.18 m²: surface area of silo
i. SA(silo)=2πrh+2πr²
ii. SA(silo) = 2π(2.5)(14) + 2π(2.5)²
iii. SA(silo) = 259.18
iv. SA(silo - door) = 259.18 - 15
v. SA(silo - door) = 244.18
3.
a. 712.18 m²: total surface area painted red
i. add both surface areas: 468 + 244.18 = 712.18 m²
hope this helps :)
