Answer:
Second picture: y=4 and x=7
First picture: x=70 degrees y=20 degrees
Explanation:
Second picture:
One of the given triangles is an equilateral and the other is an isosceles.
Equilateral triangle has all congruent sides and it's angles are all congruent.
Isosceles triangle has two congruent angles and the opposite sides of those congruent angles are also congruent.
This implies all the side algebraic expression-measurements given are all equal.
5y-4=y+12
Add 4 on both sides:
5y=y+16
Subtract y on both sides:
4y=16
Divide both sides by 4:
y=4
So what is the side measurement for each of the sides given in terms of algebraic expressions?
y+12
4+12
16
Each side given in terms of an algebraic explanation is 16 units.
So we have also the following equation to solve:
3x-5=16
Add 5 on both sides:
3x=21
Divide both sides by 3:
x=7
So x=7 and y=4.
There is only one side in the picture that is possibly not 16. It is the one of the sides in the isosceles, not opposite the base angles.
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First picture:
We are given x+y=90.
Since that one triangle is an isosceles we know that x+x+(180-40)=180
So let's solve the second equation for x then go back and solve for y in the first equation.
2x+140=180
Subtract 140 on both sides:
2x=40
Divide both sides by 2:
x=20
First equation:
x+y=90
So y=90-x=90-20=70.