Answer:
x = 2 ± (i)√5 (Answer b)
Step-by-step explanation:
x²-4x+9=0 can be solved in a variety of ways; the first two that come to mind that are also appropriate are (1) completing the square and (2) using the quadratic formula.
Completing the square is fast here:
Rewrite x²-4x+9=0 as x²-4x +9=0
Identify the coefficient of the x term: it is -4
Take half of that, obtaining -2
Square this result, obtaining 4
Add 4 to x²-4x +9=0, in the blank space in the middle, and then subtract 4: x²-4x +4 -4 +9=0
Rewrite x²-4x +4 as the square of a binomial:
(x - 2)² - 4 + 9 = 0 → (x - 2)² = -5
Take the square root of both sides: x - 2 = ±√(-5) = ± (i)√5
Then x = 2 ± (i)√5
Answer:
El ascensor recorrió unos 39 metros
Step-by-step explanation:
Segun la pregunta cada cada piso tiene 3 metros de altura, por lo tanto para calcular los metros que recorrió el ascensor tenemos que hacer el siguiente calculo:
metros desde el primer piso al quinto piso=3 metros*4=12 metros
metros desde el quinto piso al segundo piso=3 metros*3=9 metros
metros desde el segundo piso al octavo piso=3 metros*6=18 metros
Por lo tanto los metros que recorrió el ascensor=12 metros+9 metros+18 metros
metros que recorrió el ascensor=39 metros
El ascensor recorrió unos 39 metros
Answer:
50.80 cm^3
Step-by-step explanation:
the polyhedron is a rectangular pyramid
Volume of a rectangular pyramid = 1/3 x ( width x height x length)
1/3 ( 4 x 5 x 3) = 20 inches
we need to convert inches to cm
1 in = 2.54 cm
20 x 2.54 = 50.80 cm^3
Answer:
The answer is 6/24
Step-by-step explanation:
1/3 was multiplied by 3 so should the other one too.
65 % ------------------ 23.4 items
100 % ----------------- x items
65 : 100 = 23.4 : x
65 x = 100 * 23.4
65 x = 2340
x = 2340 : 65
x = 36
Answer: there were 36 items on the test.