Question:
The square of a number decreased by 3 times the number is 28 find all possible values for the number
Answer:
The possible values of number are 7 and -4
Solution:
Given that the square of a number decreased by 3 times the number is 28
To find: all possible values of number
Let "a" be the unknown number
From given information,
square of a number decreased by 3 times the number = 28


Let us solve the above quadratic equation


Using the above formula,


Thus the possible values of number are 7 and -4
<span>The discriminant of a quadratic equation is the b^2-4ac portion that the square root is taken of. If the discriminant is negative, then the function has 2 imaginary roots, if the discriminant is equal to 0, then the function has only 1 real root, and finally, if the discriminant is greater than 0, the function has 2 real roots. So let's look at the equations and see which have a positive discriminant.
f(x) = x^2 + 6x + 8
6^2 - 4*1*8
36 - 32 = 4
Positive, so f(x) has 2 real roots.
g(x) = x^2 + 4x + 8
4^2 - 4*1*8
16 - 32 = -16
Negative, so g(x) does not have any real roots
h(x) = x^2 – 12x + 32
-12^2 - 4*1*32
144 - 128 = 16
Positive, so h(x) has 2 real roots.
k(x) = x^2 + 4x – 1
4^2 - 4*1*(-1)
16 - (-4) = 20
Positive, so k(x) has 2 real roots.
p(x) = 5x^2 + 5x + 4
5^2 - 4*5*4
25 - 80 = -55
Negative, so p(x) does not have any real roots
t(x) = x^2 – 2x – 15
-2^2 - 4*1*(-15)
4 - (-60) = 64
Positive, so t(x) has 2 real roots.</span>
Answer:
the probability that the average diameter of those sand dollars is more than 4.73 centimeters is 0.5910
Step-by-step explanation:
Given information:
mean, x = 5
standard deviation, σ = 0.9
number of sample, n = 16
now we calculate the probability that the average diameter of those sand dollars is more than 4.73 centimeters.
P(x>4.73) = P (z > (4.73 - x) / (σ
)
= P (z > (4.73 - 4) / (0.9
)
= P (z > 0.203)
= 0.5910
Answer:
B - Her monthly average would have increased by $19.57. ... Katie works as a waitress and records her monthly tips in the table shown below. If Katie decided not to work the month of November, how would her five month average compare to her six month ... Lisa is currently taking physics as one of her electives in school.
Step-by-step explanation:
<span>Most ancient societies had symbols to represent numbers, but they did not have symbols to represent operations or unknown quantities. Thus, the problems and solutions to the problems had to be written in word form.</span>