Answer: 100 i think, but am not sure.
Step-by-step explanation:
The formula for area of a rectangle is A=l*w. Since the area is 84, then you can use the A=l*w formula. 84 = x(x+8) would be the equation to solve for x.
Now, you need to put the equation in standard form. So, x2 + 8x - 84 = 0.
Since you can't solve this quadratic using factoring, you need to complete the square.
To complete the square you need to add 84 to both sides. Now you have x2 + 8x = 84. Take the coefficient for the x term (8) and divide by 2. Now square it. That would be 42, so 16. Now you have x2 +8x +16 = 100.
Factor x2 +8x +16, so (x+4)2 = 100
If you use the square root property, you have x+4 = 10. Therefore, x = 6 (the short side) and 14 is the long side.
Answer:
2nd 3rd and last option
Step-by-step explanation:
2.
3.
6.
Answer:
Step-by-step explanation:
we know that
Heron's Formula is a method for calculating the area of a triangle when you know the lengths of all three sides.
so
where
a, b and c are the length sides of triangle
s is the semi-perimeter of triangle
we have
<em>Find the semi-perimeter s
</em>
s=
Find the area of triangle
simplify
Answer:
b = 3 and a = -1
Step-by-step explanation:
You have your given equation:
2a - 3b = -11
a + 3b = 8
You need to find what a and b is.
To find b:
2a - 3b = -11
-2a - 6b = -16
I multiplied a + 3b = 8 by -2. When you multiply a number you have to multiply all of them. You have to choose a number that would cancel out all of a.
So now your equation would look like this when you solve for b:
2a - 3b = -11
-2a - 6b = -16
-------------------
a - 9 = -27 then you divide -9 to -27 which is 3 so b = 3.
To find a:
2a - 3b = -11
a + 3b = 8
I multiplied a + 3b = 8 by -1 and 2a - 3b = -11 by -1 as well.
Your equation will look like this when you solve for a:
-2a + 3b = 11
-1a - 3b = -8
------------------
-3a = 3 then divide -3 to 3 which is -1 so a = -1.
Check to see if you have the correct answer by plugging in the number you got for a and b into the equation and solve.
1. 2(-1) -3(3) = -11
-2 - 9 = -11
2. -1 + 3(3) = 8
-1 + 9 = 8
Answer:
Everything is x2 itself.
Step-by-step explanation:
5x2=10 10x2=20 20x2=40
