please help! geometry question!
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Answer:
Step-by-step explanation:
∠B=∠C (isosceles triangle)
so ⊥ AD bisects BC.
or BD=CD
2x-15=x+7
2x-x=7+15
x=22
AD=4x-6=22×4-6=82
DC=22+7=29
[tex]AC=\sqrt{(82^2+29^2)} =\sqrt{6724+841} =\sqrt{7565} \approx 86.977 \approx 86.98[/tex]