Use the formula 0 = b^2-4ac
0 = -b^2-4(2)(-9)
0 = -b^2+72
b^2 = 72
b = square root of 72
b = 2 real numbers
Answer:
The height of the triangle is
cm.
Step-by-step explanation:
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The formula for solving the area of a triangle is
where
stands for base and
stands for height.
Let's substitute 30
for the area and 10 for the base.

-------------------->>>>
Now, let's solve to find the height.

Multiply
times 

Divide both sides by 5.

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Hope this is helpful.
Answer:
ans = 112
Step-by-step explanation:
Hope it will help
please mark as brainlists
Answer:
A
Step-by-step explanation:
We can find the surface area of the object by adding the surface areas of each part. We have many rectangle faces to count and two triangular faces. Each has a formula for the area. We will find the area of each and then add them all together.
Triangle - 0.5 *b*h
Rectangle - b*h
<u>Triangles</u>
There are two triangles on either side. The height is 1.5. The base is 1.8.
0.5(1.5)(1.8)=1.35 meters squared
Since there are two, we will add 1.35+1.35 in our final calculation.
<u>Rectangles</u>
We will start by calculating the largest rectangle on the side. It has height of 4 and a base of 2.5 (shown above left).
4(2.5)=10
Since there are two (one we can see and one we can't), we will add 10+10 in our final calculation.
Next we calculate the top and bottom. The height is 3 and the base is 2.5 on top. But the bottom sticks out more and adds 1.8 to its base.
Top - 3(2.5)=7.5
Bottom-3(2.5+1.8)=12.9
Finally, we will calculate the front side and back(not visible) as well as the slant up front. The back side has height 4 and base 3. The front side has base 3 and height 4-1.5=2.5. The slant has base 2.3 and height 3.
Back - 4(3)=12
Front- 3(2.5)=7.5
Slant - 3(2.3)=6.9
We add all together for the total surface area: 1.35+1.35+10+10+7.5+12.9+12+7.5+6.9=69.5 meters squared.