Question

Gasiti numarul natural y daca :(8×y^2-400):20=20 (3×y^2+8)×4=44

Answer 1

(8×y^2-400):20=20

8×y^2-400=20×20

8×y^2=400+400

y^2=800÷8

y^2=100=>y=radical din 100 =>y=10

(3×y^2+8)×4=44

3×y^2+8=44÷4

3×y^2=11-8

y^2=3÷3

y=radical din 1 =>y=1

Answer 2

Răspuns

Explicație pas cu pas:

( 8 × y² - 400 ) : 20 = 20

8 × y² - 400 = 20 × 20

8 × y² - 400 = 400

8 × y² = 400 + 400

8 × y² = 800

y² = 800 : 8

y² = 100 = 10²

y = 10

____________________________

( 3 × y² + 8 ) × 4 = 44

3 × y² + 8 = 44 : 4

3 × y² = 11 - 8

3 × y² = 3

y² = 3 : 3

y² = 1 = 1²  ⇒   y = 1