The graph of the function y = x2 + 4 and a straight line PQ are drawn to solve the equation x2 - 3x + 2 = 0. What is the equation of PQ?
Answer Details
To solve the equation x^2 - 3x + 2 = 0, we can factor it into (x - 1)(x - 2) = 0. This means that x = 1 or x = 2.
Now, we can plug these values of x into the equation y = x^2 + 4 to get the corresponding y values. When x = 1, y = 5 and when x = 2, y = 8.
We also know that the line PQ intersects the graph of y = x^2 + 4 at two points, since the equation x^2 - 3x + 2 = 0 has two solutions.
Since the line PQ is a straight line, we can find its equation by using the slope-intercept form, y = mx + b, where m is the slope and b is the y-intercept.
To find the slope, we can use the two points of intersection between PQ and the parabola, which are (1, 5) and (2, 8). The slope is the change in y over the change in x, which is (8 - 5)/(2 - 1) = 3.
To find the y-intercept, we can plug in the coordinates of one of the points into the slope-intercept form and solve for b. Using (1, 5), we get:
5 = 3(1) + b
b = 2
So the equation of PQ is y = 3x + 2, which is.