Answer:
Step-by-step explanation:
the error was in not take the root of the number correctly
the student assumes that the root of 144 was equal to 72
Let <em>a</em> and <em>b</em> be the two numbers. Then
<em>a</em> + <em>b</em> = -4
<em>a b</em> = -2
Solve the second equation for <em>b</em> :
<em>b</em> = -2/<em>a</em>
Substitute this into the first equation:
<em>a</em> - 2/<em>a</em> = -4
Multiply both sides by <em>a</em> :
<em>a</em>² - 2 = -4<em>a</em>
Move 4<em>a</em> to the left side:
<em>a</em>² + 4<em>a</em> - 2 = 0
Use the quadratic formula to solve for <em>a</em> :
<em>a</em> = (-4 ± √(4² - 4(-2))) / 2
<em>a</em> = -2 ± √6
If <em>a</em> = -2 + √6, then
-2 + √6 + <em>b</em> = -4
<em>b</em> = -2 - √6
In the other case, we end up with the same numbers, but <em>a</em> and <em>b</em> are swapped.
x = number of weeks which is some positive whole number
50x = amount saved after x weeks, when saving $50 per week
50x+800 = add on the 800 she already has
The expression 50x+800 is the total money saved. We set this equal to the 1150 to set up the equation we're after
<h3>Answer: 50x+800 = 1150</h3>
The secant of the angle through a point (-5, 3) is -13/5
<h3>Equation of a circle</h3>
The equation of a circle with center (0,0) is given by
x² + y² = r² where r = radius of circle
Now, comparing this to the equation of the given circle x² + y² = 169,
⇒ r² = 169
r = √169
r = 13
<h3>Secant of angle </h3>
The secant of the angle through a point (x, y) is secФ = r/x where
- r = radius of circle and
- x = x-coordinate of point
Now for the point A(-5,12), x = -5.
Since r = 13
secФ = r/x
= 13/-5
= -13/5
So, The secant of the angle through a point (-5, 3) is -13/5
Learn more about secant of an angle here:
brainly.com/question/14910565
Answer:
Between 149 and 151
Step-by-step explanation:
25 x 6 = 150
150 is between 149 and 151.
