All these equations are in the form of ax^2 + bx + c = 0, where a, b, and c are some numbers. the discriminants of equations like this are equal to b^2 - 4ac. if the discriminant is negative, there are two imaginary solutions. if the discriminant is positive, there are two real solutions. if the discriminant is 0, there is one real solution.
<span>x^2 + 4x + 5 = 0
</span>b^2 - 4ac
4^2 - 4(1)(5)
16-20
-4, two imaginary solutions.
<span>x^2 - 4x - 5 = 0
</span>b^2 - 4ac
(-4)^2 - 4(1)(-5)
16 + 20
36, two real solutions.
<span>4x^2 + 20x + 25 = 0
</span>b^2 - 4ac
20^2 - 4(4)(25)
400 - 400
0, one real solution.
9514 1404 393
Answer:
- Slant Height = 20.1 km
- Radius = 9 km
- Lateral Area = 568.3 km²
Step-by-step explanation:
The slant height is read from the diagram as 20.1 km.
The radius is half the diameter, so is 9.0 km.
The lateral area is ...
A = πrs = π(9.0 km)(20.1 km) ≈ 568.3 km²
__
Desmos uses r for a special purpose, so we have used r₁ to signify the radius of the cone. The "round" function works only to round to an integer, so special effort must be used to get rounding to 1 decimal place.
Answer:
3
Step-by-step explanation:
to evaluate substitute x = 4 into the rational expression, that is
=
= 3
Answer:
Step-by-step explanation:
2k+10 | Both terms share the common factor two, so you can take it out (divide both terms by 2)
2(k+5) | Now if you use the Distributive Property to double check, you get 2k+ 10 again