Equal Binomial Coefficients

In the expansion of $(1+x{)}^{43}$ the coefficients of the $(2r+1{)}^{\text{th}}$ and the $(r+2{)}^{\text{th}}$ terms are equal; find $r$.

H. S. Hall & S. R. Knight, Higher Algebra (1891) · Ch. XIII. Binomial Theorem: Positive Integral Index, Examples XIII.b, No. 14