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Answer:
(a) x = (3 -ln(3))/5 ≈ 0.819722457734
(b) y = 10
Step-by-step explanation:
(a) Taking the natural log of both sides, we have ...
2x +1 = ln(3) +4 -3x
5x = ln(3) +3 . . . . . . . . add 3x-1
x = (ln(3) +3)/5 ≈ 0.820
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(b) Assuming "lg" means "log", the logarithm to base 10, we have ...
log(y -6) +log(y +15) = 2
(y -6)(y +15) = 100 . . . . . . . taking antilogs
y^2 -9x -190 = 0 . . . . . . . . eliminate parentheses, subtract 100
(y -19)(y +10) = 0 . . . . . . . . factor
The values of y that make these factors zero are -19 and 10. We know from the first term that (y-6) > 0, so y > 6. That means y = -19 is an extraneous solution.
The solution is ...
y = 10
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When solving equations using a graphing calculator, it often works well to define a function f(x) such that the solution is f(x) = 0, the x-intercept(s). That form is easily obtained by subtracting the right side of the equation from both sides of the equation. In part (a) here, that is ...
f(x) = e^(2x+1) -3e^(4-3x)
20 I apologize if this is wrong
If two fractions have the same numerator, the fraction with the smaller denominator is bigger.
3/8 is bigger.
Our discriminant is 0 so, 
has one real root.
Option C is correct.
Step-by-step explanation:
we need to find the discriminant and the number of real roots for the following equation:
The discriminant is found by using square root part of quadratic formula:
where b =12, a=4 and c=9
Putting values:
To find out the number of real roots using discriminant we have following rules:
- if discriminant b^2-4ac >0 then 2 real roots
- if discriminant b^2-4ac =0 then 1 real root
- if discriminant b^2-4ac <0 then no real roots
Since our discriminant b^2-4ac is 0 so, has one real root.
Option C is correct.
Keywords: discriminant
Learn more about discriminant at:
#learnwithBrainly
Slope of a line can be determined using this formula
m = (y₂ - y₁) / (x₂ - x₁)
From the question, we know that
(x₁,y₁) = (2,-3)
(x₂,y₂) = (2,9)
plug the numbers into the formula
m = (y₂ - y₁) / (x₂ - x₁)
m = (9 - (-3)) / (2 - 2)
m = (9 + 3) / (2 - 2)
m = 12/0
m = undefined
The pairs must form a vertical line
