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
Let
x----------> number of weeks
y----------> saved money
we now that
<span>Michael begins with $20 and saves $5 per week
so
y=20+5x------> equation 1
and
</span><span>Lindsey begins with no money, but saves $10 per week
</span><span>y=10x-------> equation 2
</span><span>the number of weeks it will take for Lindsey and Michael to save the same amount of money is when equation 1 is equals to equation 2
</span>
therefore
20+5x=10x------> 10x-5x=20------> 5x=20-----> x=20/5-----> x=4 weeks
the answer is
4 weeks
86%
Step by step explanation This is how I got the answer to your question and I gave you the solution I hope this helps you out
Answer: The distance between the girls is 362.8 meters.
Step-by-step explanation:
So we have two triangle rectangles that have a cathetus in common, with a length of 160 meters.
The adjacent angle to this cathetus is 40° for Anna, then the opposite cathetus (the distance between Anna and the tower) can be obtained with the relationship:
Tan(A) = opposite cath/adjacent cath.
Tan(40°) = X/160m
Tan(40°)*160m = 134.3 m
Now, we can do the same thing for Veronica, but in this case the angle adjacent to the tower is 55°
So we have:
Tan(55°) = X/160m
Tan(55°)*160m = X = 228.5 m
And we know that the girls are in opposite sides of the tower, so the distance between the girls is equal to the sum of the distance between each girl and the tower, then the distance between the girls is:
Dist = 228.5m + 134.3m = 362.8m
4 and -2.5
You can get this by first factoring the equation.
(2x + 5)(x - 4)
Then set both equal to zero and solve individually.
