Create equations:
10X+15y=2575.
X+Y=210.
Solve for X: X=210-Y, and sub it into the other equation: 10(210-Y)+15Y=2575. Solve for Y: 2,100-10y+15y=2575, 5y=475, y=95.
Sub Y into the original problem: X+95=210. Solve: X=115.
The first mechanic charges $115 per hour and the second charges $95 :)
R = (2s - 6t + 5)/2
2R = 2s - 6t + 5
2s = 2R + 6t - 5
s = (2R + 6t - 5)/2
1cm means 1 centimeter
centi=1000 so
1cm=1/1000m
1m=1000cm
so 27cm+1m+80cm=27cm+1000cm+80cm=1107cm=1.107m
Answer:
Step-by-step explanation:
In each case we find the discriminant b^2 - 4ac.
If the discriminant is negative, we have two unequal, complex roots.
If the discriminant is zero. we have two equal, real roots.
If the discriminant is positive, we have two unequal real roots.
#51: 8v^2 - 12v + 9: the discriminant is (-12)^2 - 4(8)(9) = -144. we have two unequal, complex roots
#52: (-11)^2 - 4(4)(-14) = 121 + 224 = 345. we have two unequal real roots.
#53: (-5)^2 - 4(7)(6) = 25 - 168 (negative). we have two unequal, complex roots.
#54: (4)^2 - 16 = 0. We have two equal, real roots.