Which lines are perpendicular?

Line A: y =
1
2
x + 2
Line B: y =
−1
2
x + 7
Line C: y = 2x + 4
Line D: y =
1
2
x +
5
4

Line A: y =
1
2
x + 2
Line B: y =
−1
2
x + 7
Line C: y = 2x + 4
Line D: y =
1
2
x +
5
4
Which lines are perpendicular?

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With these 5 geometry questions! pls 1.)quadrilateral abcd is inscribed in this circle.what is the measure of ∠a ? enter your answer in the box.°2.)quadrilateral abcd is inscribed in a circle.what is the measure of angle a? enter your answer in the box.m∠a= 3.)quadrilateral abcd is inscribed in this circle.what is the measure of angle b? enter your answer in the box.m∠b= °4.)quadrilateral abcd is inscribed in this circle.what is the measure of angle a? enter your answer in the box.°5.) quadrilateral abcd is inscribed in this circle.what is the measure of angle c? enter your answer in the box.°

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