, that is D
when multiplying like variables add the exponents
=
= 
Alright here it is:
-2/7x + y = -7
Answer: 225
Step-by-step explanation: If the whole area is 900 square inches you divide by the sides of the square 4 and divide by the total area 900. 900/4 = 225
Answer:
a) (+) × (?) = (+)
(?) = (+)
b) (-) × (+) = ?
? = (-)
c) (?) × (-) = ?
? is undefined
Step-by-step explanation:
a) (+) × (?) = (+)
From the given equation in the question, by dividing both side of the equation by (+), we have;
((+) × (?))/(+) = (+)/(+)
(?) = (+)/(+) = (+)
Therefore, we have;
(+) × (+) = (+)
(?) = (+)
b) (-) × (+) = ?
From the given equation in the question we apply the operation rules as follows;
(-) × (-) = (+)
(-) × (+) = (-)
Therefore;
(-) × (+) = ? = (-)
? = (-)
c) (?) × (-) = ?
From the rules of multiplication, we have;
(-) × (-) = (+)
(+) × (-) = (-)
Therefore, when (?) = (-), ? = +, from which we have;
(?) ≠ ?, which is an error
Similarly, when (?) = (+), ? = -, therefore, (?) and ?, always changes sign
Therefore, the equation, (?) × (-) = ?, is undefined.