Math Problem Statement

(a) In the graph above, the curve (y+1)^2−x^2=8 meets the straight line 3x+2y=−5 at point P and Q. Find the coordinates of point P and Q. Coordinates of point P = (?,?) Coordinates of point Q = (?,?) (b) The straight line x3x+2y=−5 meets another line xy−2x=1 at point R. Find the coordinates of point R. Coordinates of point R = (?,?)

Solution

(a) Finding the Coordinates of Points P and Q

The problem involves finding the points of intersection between the curve (y+1)2x2=8(y + 1)^2 - x^2 = 8 and the straight line 3x+2y=53x + 2y = -5.

Step 1: Express yy from the line equation

We start by solving the line equation for yy:

3x+2y=5    2y=3x5    y=32x523x + 2y = -5 \implies 2y = -3x - 5 \implies y = -\frac{3}{2}x - \frac{5}{2}

Step 2: Substitute into the curve equation

Next, substitute this expression for yy into the curve equation (y+1)2x2=8(y + 1)^2 - x^2 = 8:

(32x52+1)2x2=8\left(-\frac{3}{2}x - \frac{5}{2} + 1\right)^2 - x^2 = 8

Simplifying the expression inside the square:

y+1=32x32    (32(x+1))2x2=8y + 1 = -\frac{3}{2}x - \frac{3}{2} \implies \left(-\frac{3}{2}(x + 1)\right)^2 - x^2 = 8

Simplifying the square:

(94(x+1)2)x2=8\left(\frac{9}{4}(x + 1)^2\right) - x^2 = 8

Expanding and simplifying:

94(x2+2x+1)x2=8    94x2+92x+94x2=8\frac{9}{4}(x^2 + 2x + 1) - x^2 = 8 \implies \frac{9}{4}x^2 + \frac{9}{2}x + \frac{9}{4} - x^2 = 8

Multiply by 4 to eliminate the fraction:

9x2+18x+94x2=329x^2 + 18x + 9 - 4x^2 = 32

5x2+18x23=05x^2 + 18x - 23 = 0

Step 3: Solve the quadratic equation

We solve the quadratic equation using the quadratic formula x=b±b24ac2ax = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}, where a=5a = 5, b=18b = 18, and c=23c = -23:

x=18±1824(5)(23)2(5)=18±324+46010=18±78410=18±2810x = \frac{-18 \pm \sqrt{18^2 - 4(5)(-23)}}{2(5)} = \frac{-18 \pm \sqrt{324 + 460}}{10} = \frac{-18 \pm \sqrt{784}}{10} = \frac{-18 \pm 28}{10}

This gives us two possible values for xx:

x1=1andx2=4.6x_1 = 1 \quad \text{and} \quad x_2 = -4.6

Step 4: Find corresponding yy values

Substitute these xx values back into y=32x52y = -\frac{3}{2}x - \frac{5}{2}:

For x1=1x_1 = 1:

y1=32(1)52=3252=82=4y_1 = -\frac{3}{2}(1) - \frac{5}{2} = -\frac{3}{2} - \frac{5}{2} = -\frac{8}{2} = -4

For x2=4.6x_2 = -4.6:

y2=32(4.6)52=13.8252=8.82=4.4y_2 = -\frac{3}{2}(-4.6) - \frac{5}{2} = \frac{13.8}{2} - \frac{5}{2} = \frac{8.8}{2} = 4.4

So, the coordinates of PP and QQ are:

Coordinates of P=(1,4)andQ=(4.6,4.4)\text{Coordinates of } P = (1, -4) \quad \text{and} \quad Q = (-4.6, 4.4)

(b) Finding the Coordinates of Point R

Now, we find the intersection of the lines 3x+2y=53x + 2y = -5 and y2x=1y - 2x = 1.

Step 1: Express yy from the second line equation

y=2x+1y = 2x + 1

Step 2: Substitute into the first line equation

Substitute y=2x+1y = 2x + 1 into 3x+2y=53x + 2y = -5:

3x+2(2x+1)=5    3x+4x+2=5    7x=7    x=13x + 2(2x + 1) = -5 \implies 3x + 4x + 2 = -5 \implies 7x = -7 \implies x = -1

Step 3: Find the corresponding yy value

Substitute x=1x = -1 into y=2x+1y = 2x + 1:

y=2(1)+1=2+1=1y = 2(-1) + 1 = -2 + 1 = -1

Thus, the coordinates of RR are:

Coordinates of R=(1,1)\text{Coordinates of } R = (-1, -1)


Summary of Results:

  • Coordinates of point P = (1,4)(1, -4)
  • Coordinates of point Q = (4.6,4.4)(-4.6, 4.4)
  • Coordinates of point R = (1,1)(-1, -1)

Would you like to see any specific details or have any questions on this solution?

Related Questions:

  1. How do you determine the number of intersection points between a line and a curve?
  2. Can a quadratic equation have complex solutions, and if so, what does that mean geometrically?
  3. How does the discriminant of a quadratic equation affect the nature of its roots?
  4. What are some methods to solve a system of linear equations geometrically?
  5. How can you interpret the intersection of two conic sections in a plane?

Tip:

When solving systems of equations involving curves, substitution is a powerful method, but always simplify expressions carefully to avoid errors in the subsequent algebraic steps.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Intersection of curves and lines
Quadratic equations
System of linear equations

Formulas

Quadratic formula

Theorems

-

Suitable Grade Level

High School