Answer:
solutions at -1 and 11
Step-by-step explanation:
(-b ± √b²-4ac) / 2a
in this problem, a = 1, b = -10, c = -11
(10±√100-4(-1)(-11)) / 2(1) =
(10 + √144) / 2 = 22/2 = 11
(10 - √144) / 2 = -2 / 2 = -1
Answer:
28
Step-by-step explanation:
5+5=10
9+9=18
10+18=28
5* 2.5= 12.5, 3/4 of 3.5 is 2.625. add those to get 15.125. divide by the hours(3.25) and the answer is- 4.65 km/hr
Answer:
The surface area of the pyramid in exact form is 64 +
cm²
The approximated surface area of the pyramid is 174.9 cm²
Step-by-step explanation:
The surface area of the square pyramid is the sum of the area of the base and the area of the four triangular faces
In Δ EFD
∵ m∠EFD = 90°
∵ m∠FDE = 60°
∵ ED = 8 cm
- By using sine ratio to find FE
∵ sin(∠FDE) = 
∴ sin(60) = 
- Multiply both sides by 8
∴ FE = 8 sin(60°)
∴ FE =
cm
In Δ AED
∵ AE = ED
∵ m∠D = 60°
- In any isosceles Δ if measure of an angle is 60, then the
triangle is equilateral Δ
∴ Δ AED is an equilateral Δ
∴ AD = 8 cm
∵ The pyramid has 4 identical triangular faces
∵ Area of each Δ =
× base × height
∵ AD is the base and FE is the height
∴ Area of each Δ =
× 8 × 
∴ Area of each Δ =
cm²
∵ Surface area of the pyramid = Area of base + 4 area of a Δ
∵ Area of base = 8²
∴ Area of base = 64 cm²
∴ Surface area of the pyramid = 64 + 4 × 
∴ Surface area of the pyramid = 64 + 
The surface area of the pyramid in exact form is 64 +
cm²
The approximated surface area of the pyramid is 174.9 cm²
Answer:
one
Step-by-step explanation:
for general form : ax²+bx+c=0
delta = b²-4ac
so for this example delta is 8²-4×2×8 =0
we know if delta = 0 , we have just one real number solution
so the answer is 1