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: 4/9 of the class are boys and 5/9 of the class are girls.
Step-by-step explanation:
- There are 9 nine students in total in the class since 4 + 5 = 9.
- Input the amount of boys and girls there are in the class in the numerator and have 9 as the denominator. 4/9 of the class are boys and 5/9 of the class are girls.
Answer:
Step-by-step explanation:
Rising 30 feet for every 400 feet of track is not a very large angle of elevation. We set this up as a right triangle to use right triangle trig to solve for the missing angle. The height is 30 and the hypotenuse is 400. The height is the side opposite the angle in question, and the hypotenuse is the hypotenuse! This is the sin ratio. Setting up the ratio using our info:

When you are looking for a missing angle measure, as we are here, use the 2nd-->sin buttons to find the inverse of sin, which looks like this:

Enter in the fraction 30/400 after the parenthesis and then hit enter to get the angle measure of 4.3 degrees.
Answer:
$1,700
Step-by-step explanation:
Multiply the rate that money is being taken out at by the amount taken out at
12 x 150
He gets 7.80 an hour so you multiply 7.8 by 5.25 hours