There is no common factor between 15, 17 and 18 because 17 is prime.
15z² +17z - 18 =
d = 17² - 4.15.-18
d = 289 + 1080
d = 1369
z = (-17 +/- \/1369) : 2 * 15
z = (-17 + 37) : 30
z' = 20 : 30 = 2/3
z" = (-17 - 37) : 30
z" = -54 : 30 = -1.8
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Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation;
3*n-4-(14)=0
Pull out like factors :
3n - 18 = 3 • (n - 6)
Solve : 3 = 0
This equation has no solution.
A a non-zero constant never equals zero.
Solve : n-6 = 0
Add 6 to both sides of the equation :
n = 6
The old photocopier can make x manuals in an hour. The new photocopier can make 4x. Combined, they made 5x manuals in an hour.
In one hour they can make 1/28 of the manuals.
1/(28*5)=1/140 is the rate.
The new photocopier can make all the manuals in 4/140 or 35 hours.
The old one can make them in 140 hours.
Answer:
This is true.
Congruent triangles have the same shape and the same size. So, you can position them so that one is superimposed (line up perfectly) on the other.
