Answer:
Step-by-step explanation:
If all 21 coins were dimes, she'd have $2.10. But she has 90 more cents than that. Now for each coin that's a quarter, not a dime, she has 15 cents more. 90/15= 6. So there are 6 quarters, and 21-6 = 15 dimes.
Now we do it backwards to see if it's right. 6 quarters is $1.50, 15 dimes is $1.50, add those together and you get $3. So it's right. 6 quarters, 15 dimes.
Answer:
256h28k8
Step-by-step explanation:
t=45min
d=4km
45min/60min = 0.75 hours
v=d/t
v=4km/0.75hours
v=5.33km/hour. So the answer is B. 45 minutes.
The equation in slope-intercept form for the line that passes through the point ( -1 , -2 ) and is perpendicular to the line − 4 x − 3 y = − 5 is 
<em><u>Solution:</u></em>
<em><u>The slope intercept form is given as:</u></em>
y = mx + c ----- eqn 1
Where "m" is the slope of line and "c" is the y - intercept
Given that the line that passes through the point ( -1 , -2 ) and is perpendicular to the line − 4 x − 3 y = − 5
Given line is perpendicular to − 4 x − 3 y = − 5
− 4 x − 3 y = − 5
-3y = 4x - 5
3y = -4x + 5

On comparing the above equation with eqn 1, we get,

We know that product of slope of a line and slope of line perpendicular to it is -1

Given point is (-1, -2)
Now we have to find the equation of line passing through (-1, -2) with slope 
Substitute (x, y) = (-1, -2) and m = 3/4 in eqn 1



Thus the required equation of line is found
In general, you cannot prove that because it is not true.
2 is rational. √2 is not.