L G Determine Equation Of Line Determine eqn

L. G. Determine Equation Of Line Determine eqn. of line with the help of a slope and y-intercept. Determine eqn. of line with the help of two points. Determine eqn. of line with the help of slope and one point.

Success Criteria: • I can write the equation of line with the help of slope and y-intercept. • I can write the equation of line by using two points on line. • I can write the equation of line with the help of slope and one point.

Agenda: Introduction. Linear Work equation video. in groups for inquiry based learning. Determine the eqn. of line from the given information. Review. Distribution of Gold, Silver and bronze medals.

Equation of line can be represented as: ax+ by + c = 0 Standard form y = mx + b Slope form Where m = slope b = y-intercept

Case 1: Given: slope y- intercept m b Example: Determine the equation of a line which has slope of 4 and y-intercept 3 ? Slope m=4 Y- intercept b=3 Step 1: Write the equation in slope form. y = mx + b Step 2: Insert the values in the equation. y = 4 x + 3

Find the equation of the line that has a slope of -1/3 and the same y-intercept as the line 2 x - 4 y + 7 = 0. y = mx + ___ Step 1: Insert the value of m y = -1/3 x + b Step 2: Find the value of y-intercept Use 2 x – 4 y + 7 = 0 to calculate y- intercept : Put x = 0 2 (0) – 4 y + 7 = 0 0 – 4 y + 7 = 0 -4 y = -7

y = -7/-4 y = 7/4 Eqn. of line : y = - 1/3 x + 7/4 Case 2 : Given: 2 points Determine the equation of a line that passes through points A (1, 9) and B (2 , -7). Step 1: Find slope m = y₂ - y₁ = -7 – 9 = - 16 x₂ - x₁ m = -16 2 -1 1

The eqn. will become : y = - 16 x + b Step 2: Calculate y- intercept by inserting the values of x and y from one point. 9 = - 16(1) + b 9 = -16 + b 9 + 16 = b 25 = b Insert the value of b in eqn. y = -16 x + 25

Determine the equation of a line which passes through points (-3, -3) and (-3, 2) m = -1/0 m = undefined Plot the graph:

Case 3: Given : slope one point Find the eqn. of a line which has slope of -1/4 and passes through a point (2, 5) y = mx+ b Step 1: Insert the value of slope in eqn. y= -1/4 x + b Step 2 : Find the y-intercept by plugging in the values of x and y. 5 = -1 (2) + b 4 5 =-2+b b=7 Eqn. : y=-1/4 x+7

Practice questions: Pg. 291 Q 5. , Pg. 292 Q 7(c), Q 8(a) & Q 10. Review. Gold, silver and bronze medal.