FIND THE INTERCEPTS OF THE LINE 3X 4Y 24.

• X-INTERCEPT: THE X-COORDINATE OF THE POINT AT WHICH A LINE CROSSES THE X-AXIS

• Y-INTERCEPT: THE Y-COORDINATE OF THE POINT AT WHICH A LINE CROSSES THE Y-AXIS

• YOU CAN FIND THE INTERCEPTS OF A LINE FROM ITS EQUATION.

• THEN YOU CAN USE THE INTERCEPTS TO GRAPH THE LINE.

• FOR THE X-INTERCEPT LET Y BE 0

• 3X 4Y 24

• 3X+4(0)=24

• 3X=24

•=• X=8

• (8,0)

• FOR THE Y-INTERCEPT LET X BE 0

• 3X 4Y 24

• 3(0)+4Y=24

• 4Y=24

•=• Y=6

• (0,6)

TWO OTHER FORMS OF EQUATIONS• STANDARD FORM

• AX+BY=C

• A AND B ARE BOTH WHOLE NUMBERS

• X AND Y ARE BOTH ON SAME SIDE OF EQUATION

• POINT SLOPE FORM

• (Y1-Y2)=M(X1-X2)

• THE TWO POINTS ARE (X,Y) AND (X,Y)

WHY DO WE NEED ALL THREE

• WE CAN USE ONE TYPE OF EQUATION TO GET TO OTHER TYPE

• DEPENDING ON INFORMATION GIVEN WE CAN CREATE ONE TYPE AND CONVERT TO ANOTHER

SOME EXAMPLES• IF GIVEN TWO POINTS (1,2)(3,4)

• YOU CAN CREATE POINT SLOPE FORM

• SLOPE ===1

• SO (Y-Y)=M(X-X)

• (4-2)=1(3-1)

GO TO STANDARD FORM• IF GIVEN TWO POINTS (1,2)(3,4)

• SLOPE ===1

• CHOOSE ONE POINT TO USE

• (Y-4)=1(X-3)

• DISTRIBUTE

• (Y-4)=(X-3)

• ADD 4 TO BOTH SIDES

• Y=X+1, NOW YOU ARE IN SLOPE INTERCEPT FORM

YOU CAN CONVERT BETWEEN ALL THREE

• YOU CAN FIND SLOPE WITH ALL THREE

• YOU CAN FIND Y AND X INTERCEPTS IN ALL FORMS

• YOU CAN GRAPH FROM ALL THREE FORMS

EXIT TICKET

• WRITE EXAMPLE OF ALL THREE TYPES OF EQUATIONS