52+23=75
10+78=88
88+75=163
that's one way
Answer:
Step-by-step explanation:
original price = 20
Answer: old McDonald has 54 chickens and 2 cows.
Step-by-step explanation:
Let x represent the number of chickens that old McDonald have.
Let y represent the number of cows that old McDonald have.
He counted 56 heads. A chicken and a cow has one head each. It means that
x + y = 56
He counted 116 legs. A chicken has 2 legs and a cow has 4 legs. It means that
2x + 4y = 116 - - - - - - - - -1
Substituting x = 56 - y into equation 1, it becomes
2(56 - y) + 4y = 116
112 - 2y + 4y = 116
- 2y + 4y = 116 - 112
2y = 4
y = 4/2 = 2
x = 56 - y = 56 - 2
x = 54
Sin 2 x + 2 sin x = 0
2 sin x cos x + 2 sin x = 0 / : 2
sin x cos x + sin x = 0
sin x ( cos x + 1 ) = 0
sin x = 0, cos x + 1 = 0, cos x = - 1;
Answer:
x = 0, or x = π
