Yes if they relate to one another using an = sign
Answer:
X=20
Step-by-step explanation:
Answer:
4 and 9
Step-by-step explanation:
let their ages be x and x - 5, then in 4 years their ages will be
x + 4 and x - 5 + 4 = x - 1 , and the product is 104, thus
(x + 4)(x - 1) = 104 ← expand factors on left using FOIL
x² + 3x - 4 = 104 ( subtract 104 from both sides )
x² + 3x - 108 = 0 ← in standard form
(x + 12)(x - 9) = 0 ← in factored form
Equate each factor to zero and solve for x
x + 12 = 0 ⇒ x = - 12
x - 9 = 0 ⇒ x = 9
However, x > 0 ⇒ x = 9
Thus
Their present ages are 9 and 9 - 5 = 4
Answer:

80 is the number in the square root
Step-by-step explanation:

To find the cross product, you can set this up as a proportion. Please see the attached paper for one of the proportions you could use.
You would then multiply the numbers that are diagonal from each other.
You would have 21(8) = 12x or
168=12x.