NSString *equation = @"15+14==29";

NSPredicate *pred = [NSPredicate predicateWithFormat:equation];

NSExpression *LeftExp = [pred leftExpression];

NSExpression *RightExp = [pred rightExpression];

NSNumber *left = [LeftExp expressionValueWithObject:nil context:nil];

NSNumber *right = [RightExp expressionValueWithObject:nil context:nil];

if ([left isEqualToNumber:right]) {
NSLog(@"yes left is equal to right");
}
else{
NSLog(@"yes left is NOT equal to right");

}

NSLog(@"left %@", left);

NSLog(@"right %@", right);