Opposite angles formed by two intersecting lines are equal, so angle 1 is the same as angle 4. That means angle 1 = angle 5 as well.
<span>When a line intersects two parallel lines, the corresponding angles are equal. That is, if r and s are parallel, then the angles formed when l intersects r are the same s the angles formed when l intersects s. Angle 1 = Angle 5, Angle 2 = Angle 6, and so forth. Since we know angle 1 = angle 5, so from that you can see that r and s are parallel</span>
<em>Hi!</em>
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<em>These can be set up as systems of equations.</em>
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<em>Let b = the number of birds, and let d = the number of dogs.</em>
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<em>b + d = 21</em>
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<em>2b + 4d = 76 (this is because birds have 2 legs and dogs have 4 legs.)</em>
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<em>You can solve this using either elimination or substitution.</em>
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<em>Consider marking brainliest.</em>
ANSWER(S):
15.51
EXPLANATION(S):
15.51 rounded to nearest tenth is 15
*more than one answer