Cross out the 2 plural nouns in the sentence below. Then rewrite the sentence using the correct form of the plural noun. Some animals, such as fishes, whales, and sea snakes, spend their entire lifes in water

substitute y = 2x - 4 to x + 2y = 12:

x + 2(2x - 4) = 12     use distributive property

x + (2)(2x) + () = 12

x + 4x - 8 = 12     add 8 to both sides

5x = 20     divide both sides by 5

x = 4

put the value of x to the first equation:

y = 2(4) - 4

y = 8 - 4

y = 4