<span>4x^2 - 25
= (2x)^2 - 5^2 .................using a^2 - b^2 = (a+b)(a-b)
= (2x + 5)(2x - 5)</span>
4 to the 1st is 4
4 to the 2nd is 16
4 to the 3rd is 64
<span>4 to the 4th is 256</span>
Hello!
You can use the Pythagorean Theorem to solve this
c is the hypotenuse
a and b are the legs
Put in the values you know
Square the numbers
Subtract 2.25 from both sides
Take the square root of both sides
b = 0.8
The answer is 0.8km
Hope this helps!
There is a way to do this algebraically using equations, but it is really messy so I am going to go over the way to do it. The way you do this is by finding whole numbers that multiply to make -192. Start with 1 and 192, 2 and 96, 3 and 64, etc and make the smaller number negative.
The reason why you make the smaller number negative is because we are looking for what numbers add together to make a positive number (10). If the bigger number was negative, then we would get a negative sum.
From what i could find, there aren't any whole numbers that satisfy this, and i doubt that the question would want you to find decimals for this.
The way to find this with equations (in short) is to have to variables, x and y, and make two equations. in this case x+y=10 and xy=-192. Solve one equation for a variable and then use substitution to plug that variable into the other equation. if you do this you get really long decimals.
