The sum of two sides of a triangle must be greater than the third side
1) 5+9>14
14>14 It is incorrect so you can’t have these lengths
2)7+7>15
14>15 X
3)1+2>4
3>4 X
4)3+6>8
9>8
6+8>3
14>3
8+3>6
11>6
So the fourth choice is correct
3(2c+d)-4(c-d)+d^2
c=1 , d=3
Use the substitution method
3(2*1+3)-4(1-3)+3^2
Multiply the brackets
3(2+3)-4+12+9
6+9-4+12+9
15-4+12+9
11+21
=32
Answer: 32
I dont know exactly what your asking but x=-y-2
By using y=mx+b you get y=-3/8x-17/8
3x(d+7) < 5d-13 (I think it is