The first equation, 8x - 9y = - 23
Obtain the equation in slope- intercept form
y = mx + c ( m is the slope and c the y-intercept )
to calculate m use the gradient formula
m = ( y₂ - y₁ ) / ( x₂ - x₁ )
with (x₁, y₁ ) = (
, 3) and (x₂, y₂ ) = (- 4, - 1 )
m =
= (- 4)/-
= 
partial equation is y =
x + c
to find c substitute either of the 2 points into the partial equation
using (- 4, - 1 ), then
- 1 = -
+ c ⇒ c = 
y =
x +
← in slope- intercept form
the equation of a line in standard form is
Ax + By = C ( A is a positive integer and B, C are integers )
rearrange the slope- intercept equation into this form
multiply through by 9
9y = 8x + 23 ( subtract 9y and 23 from both sides )
8x - 9y = - 23 in standard form
Answer:
x = 27
Step-by-step explanation:
∠ CAD and ∠ EDF are corresponding angles and are congruent, so
∠ CAD = 2x
The sum of the 3 angles in Δ ABD = 180°
sum the angles and equate to 180
72 + 2x + 2x = 180
72 + 4x = 180 ( subtract 72 from both sides )
4x = 108 ( divide both sides by 4 )
x = 27
The sum of all angles (around the black dot) is 360°
All 5 angles (if you forget the red line) are the same; so each angle is 360°/5 = 72°
So Angle 1 is 72°
Answer:
You are right.
Step-by-step explanation:
The values corresponding to x = 3 is -5.