Answer:
(a+b)^2+(a-b)^2=2(a^2+b^2)
expanding:
a² + 2ab + b² + a² -2ab + b² = 2a² + 2b²
2a² + 2b² = 2a² + 2b²
The Area is the width<span> times the </span>height<span>: A = w x h;
Then, 64 = w x h;
h = 4 + w;
64 = 4w + w^2;
w^2 + 4w - 64 = 0;
We solve this equation: w1 </span>≈ 6,24 > 0 (okay); w2 ≈ - 10,24 < 0 (not okay);
<span>Finally, h1 </span>≈ 10,24;<span>
</span>
70 / 35 = 2
So the 70 pound dog weights double the weight of the 35 pound dog, so he will eat twice as much.
2 x 2.5 = 5 cups
Meaning he will eat 5 cups of dry dog food a day.
By the same logic a 140 pound dog would have to eat twice what a 70 pound dog eats, that is 10 cups of dry dog food a day, so 7 1/2 cups are not enough.
Challenge: per pound a dog eats more than a cat. Since you know a 140 pound dog eats 10 cups, you can dive 140 by 10, to find out that each cup feeds 14 pounds, so half a cup would be the amount of food to feed a 7 pound dog, meaning that a dog weighing 1 pound less than a 8 pound cat would need the same amount of food, so it eats more than a cat.
Answer:
12
Step-by-step explanation:
Let the total number of donuts in the pack be x.
Amy = 2/3x
Anna = 1/4x
David = 1
x - 2/3x - 1/4x = 1
Find common denominators for 2/3 and 1/4
The common denominator is 12
2/3 * 4/4 = 8/12
1/4 * 3/3 = 3/12
x - 8/12x - 3/12x = 1
x - 11/12x = 1
1/12x = 1
x = 12
You can always check
Amy = 8
Anna = 3
So David must equal to 1
Hope this helps :)
Have an awesome day!