Which pair of triangles must be similar? Triangles 1 and 2 each have a 35^{\circ}35
∘
angle.

Triangles 3 and 4 are both isosceles. They each have a 40^{\circ}40
∘
angle.

Triangle 5 has a 30^{\circ}
∘
angle and a 90^{\circ}
∘
angle. Triangle 6 has a 30^{\circ}
∘
angle and a 70^{\circ}
∘
angle.

Triangle 7 has a 50^{\circ}
∘
angle and a 25^{\circ}
∘
angle. Triangle 8 has a 50^{\circ}
∘
angle and a 105^{\circ}
∘
angle.

check the picture below.

well, the angle at the vertex d is clearly not a right-angle, let's check for the one at the vertex f which does look like,   however if it's indeed, that means ef is perpendicular to df, in which case their slopes will be negative reciprocal of each other.

so the negative reciprocal of the slope of ef is 1, however the slope of df is not 1, is 1/2, so nope, they're not perpendicular lines.

step-by-step explan mxfcg'k; uafwgzfgjhklhgation:

see explanation

step-by-step explanation:

since the sequence is geometric there is a common ratio r between consecutive terms, that is

r = 4 ÷ - 2 = - 2

r = - 8 ÷ 4 = - 2

r = 16 ÷ 8 = - 2

the next term - 13 must be incorrect as it should be - 32 for the sequence to be geometric.

the first 4 terms are therefore geometric with common ratio r = - 2

the one that has a slope of 1/2 and is positive.

step-by-step explanation: 2 buckets 1 trip ; 4 buckets 2 trips and so on.