- Key -
Black tiles = x
Purple tiles = x+50
Yellow tiles = 5x
-
Total = x + x+50 + 5x = 400
⇒ 7x + 50 = 400
⇒ 7x = 400-50 = 350
⇒ x = 350/7
⇒ x = 50
Black tiles = 50
Purple tiles = 50+50 = 100
Yellow tiles = 5 x 50 = 250
(2x-3)(x+4) —> x= 3/2 x= -4
Answer:

Step-by-step explanation:
Let E be the set of all even positive integers in the universe Z of integers,
i.e
E = {2,4,6,8,10 ....∞}
be the characteristic function of E.
∴

For XE(2)
since x is an element of E (i.e the set of all even numbers)
For XE(-2)
since - 2 is less than 0 , and -2 is not an element of E
For { x ∈ Z: XE(x) = 1}
This can be read as:
x which is and element of Z such that X is also an element of x which is equal to 1.
∴

E = {2,4,6,8,10 ....∞}