It should be k= 4 or -1/3
Let a =107° and b=42°;
So cos 107° cos 42° + sin 107° sin 42° = cosa.cos42 + sina.sinb = cos(a-b)
and cos 107° cos 42° + sin 107° sin 42° = cos(107-42) = cos(65°)
Smaller x = -2/5
Larger x = 5
Answer:
y=1; x=2
Step-by-step explanation:
Substitution:
x=2y
2x+5y=9
=> if x=2y, plug in the x value into other equation, so
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2(2y)+5y=9
4y+5y=9
9y=9
y=1
You have the Y value, so now solve for X
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plug in y value to x=2y
so x=2(1)
x=2
