Riješite sustav: x + y = 4, 2x-y = 5?

Riješite sustav: x + y = 4, 2x-y = 5?
Anonim

Odgovor:

y = 1

x = 3

Obrazloženje:

# X + y = 4 # --- (1)

# 2 x-y-5 # --- (2)

Iz (1),

# X + y = 4 #

# X = 4-il # --- (3)

Pod (3) u (2)

# 2 x-y-5 #

# 2 (4-il) -y-5 #

# 8-2y-y = 5 #

# 8-3y = 5 #

# 3 = 3y #

# Y = 1 # --- (4)

Pod (4) u (3)

# X = 4-il #

# X = 4-1 #

# 3 x = #