If x/0.5 + y/0.2 = 18, where x and y are positive integers, then what is the value of x ?
1 answer:
An equation without exponents and two variables, is typically a straight line. All the points on the line with integer coordinates are solutions of the equation. Since x and y have to be positive as well, there aren't that many solutions.
Let's see where the line crosses the x-axis, it is where y=0:
x/0.5 + 0 = 18, so x=9 at the intercept. y=0 there, so this is a point on the line, but not a solution to the question (y was supposed to be positive).
Possible values for x are thus limited to 1,2,3,4,5,6 and 7. You can try them all (ie., solve the equation with them) and see for which x values the y is also positive and integer.
You will find that x=4, y=2 is the only pair that satisfies these conditions.
Let's see where the line crosses the x-axis, it is where y=0:
x/0.5 + 0 = 18, so x=9 at the intercept. y=0 there, so this is a point on the line, but not a solution to the question (y was supposed to be positive).
Possible values for x are thus limited to 1,2,3,4,5,6 and 7. You can try them all (ie., solve the equation with them) and see for which x values the y is also positive and integer.
You will find that x=4, y=2 is the only pair that satisfies these conditions.
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The length of AC is 16 km.
Solution:
Given data:
AB = c = 14 km, ∠A = 30° and ∠B = 89°
AC = b = ?
<u>Let us first find angle C:</u>
<em>Sum of all angles in a triangle = 180°</em>
m∠A+ m∠B + m∠C = 180°
30° + 89° + m∠C = 180°
119° + m∠C = 180°
Subtract 119° from both sides, we get
m∠C = 61°
<u>To find the length of AC:</u>
<em>Using sine formula:</em>
Substitute the given values in the formula.
Multiply by sin 89° on both sides.
The length of AC is 16 km.