Answer:
Step-by-step explanation:
This is one of the more interesting motion problems I've seen. I like it! If Kelly is driving north (straight up) for 9 miles, then turns east (right) and drives for 12 miles, what we have there are 2 sides of a right triangle. The hypotenuse is created by Brenda's trip, which originated from the same starting point as Kelly and went straight to the destination, no turns. We need the distance formula to solve this problem, so that means we need to find the distance that Brenda drove. Using Pythagorean's Theorem:
and
and
so
c = 15.
Brenda drove 15 miles. Now we can fill in a table with the info:
d = r x t
Kelly 12+9 42 t
Brenda 15 45 t
Because they both left at the same time, t represents that same time, whatever that time is. That's our unknown.
If d = rt, then for Kelly:
21 = 42t
For Brenda
15 = 45t
Solve Kelly's equation for t to get
t = 1/2 hr or 30 minutes
Solve Brenda's equations for t to get
t = 1/3 hr or 20 minutes
That means that Brenda arrived at the destination 10 minutes sooner than Kelly.
Answer and explanation:
Given : Expression 
as ![\sqrt[4]{16}](https://tex.z-dn.net/?f=%5Csqrt%5B4%5D%7B16%7D)
To find : Use properties of exponents to explain why it makes sense to define expression ?
Solution :
Using property of exponent,
![x^{\frac{1}{n}}=\sqrt[n]{x}](https://tex.z-dn.net/?f=x%5E%7B%5Cfrac%7B1%7D%7Bn%7D%7D%3D%5Csqrt%5Bn%5D%7Bx%7D)
On comparing with given expression,
Here x=16 and n=4
![(16)^{\frac{1}{4}}=\sqrt[4]{16}](https://tex.z-dn.net/?f=%2816%29%5E%7B%5Cfrac%7B1%7D%7B4%7D%7D%3D%5Csqrt%5B4%5D%7B16%7D)
Hence by property it defied the expression.
Well, 4 times 7 is 28 and then plus 2 is 30! Therefore, he buy at the most 7 books.
<h3>
Answer: 1.75 square feet</h3>
Work Shown:
area of the triangle on the left = base*height/2 = 0.75*2/2 = 0.75
area of the triangle on the right = base*height/2 = 0.5*4/2 = 1
total area = 0.75+1 = 1.75 square feet
Christopher purchased 2.8 pounds of almonds and 3.5 pounds to roasted pistachios.
Step-by-step explanation:
Cost of almonds per pound = $10
Cost of roasted pistachios = $12
Total amount spent = $70
Weight of nuts = 6.3
Let,
Weight of almonds = x
Weight of roasted pistachios = y
According to given statement;
x+y=6.3 Eqn 1
10x+12y=70 Eqn 2
Multiplying Eqn 1 by 10
Subtracting Eqn 3 from Eqn 2;
Dividing both sides by 2
Putting y=3.5 in Eqn 1
Christopher purchased 2.8 pounds of almonds and 3.5 pounds to roasted pistachios.
Keywords: linear equations, elimination method
Learn more about elimination method at:
#LearnwithBrainly
